161256420 has 360 divisors, whose sum is σ = 595203840. Its totient is φ = 36391680.

The previous prime is 161256419. The next prime is 161256461. The reversal of 161256420 is 24652161.

161256420 is a `hidden beast` number, since 1 + 6 + 12 + 5 + 642 + 0 = 666.

161256420 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 5201805 + ... + 5201835.

It is an arithmetic number, because the mean of its divisors is an integer number (1653344).

Almost surely, 2^161256420 is an apocalyptic number.

161256420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161256420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (297601920).

161256420 is an abundant number, since it is smaller than the sum of its proper divisors (433947420).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161256420 is a wasteful number, since it uses less digits than its factorization.

161256420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 73 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 161256420 is about 12698.6778839374. The cubic root of 161256420 is about 544.3008401242.

The spelling of 161256420 in words is "one hundred sixty-one million, two hundred fifty-six thousand, four hundred twenty".