123581620 has 12 divisors (see below), whose sum is σ = 259521444. Its totient is φ = 49432640.

The previous prime is 123581581. The next prime is 123581629. The reversal of 123581620 is 26185321.

It can be written as a sum of positive squares in 2 ways, for example, as 31651876 + 91929744 = 5626^2 + 9588^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123581629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3089521 + ... + 3089560.

It is an arithmetic number, because the mean of its divisors is an integer number (21626787).

Almost surely, 2^123581620 is an apocalyptic number.

123581620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123581620 is an abundant number, since it is smaller than the sum of its proper divisors (135939824).

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

123581620 is a wasteful number, since it uses less digits than its factorization.

123581620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6179090 (or 6179088 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 123581620 is about 11116.7270363178. The cubic root of 123581620 is about 498.1016281572.

The spelling of 123581620 in words is "one hundred twenty-three million, five hundred eighty-one thousand, six hundred twenty".