161988402 has 16 divisors (see below), whose sum is σ = 338063040. Its totient is φ = 51648432.

The previous prime is 161988401. The next prime is 161988413. The reversal of 161988402 is 204889161.

It is not an unprimeable number, because it can be changed into a prime (161988401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 586777 + ... + 587052.

It is an arithmetic number, because the mean of its divisors is an integer number (21128940).

Almost surely, 2^161988402 is an apocalyptic number.

161988402 is an abundant number, since it is smaller than the sum of its proper divisors (176074638).

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

161988402 is a wasteful number, since it uses less digits than its factorization.

161988402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1173857.

The product of its (nonzero) digits is 27648, while the sum is 39.

The square root of 161988402 is about 12727.4664407336. The cubic root of 161988402 is about 545.1231683017.

The spelling of 161988402 in words is "one hundred sixty-one million, nine hundred eighty-eight thousand, four hundred two".