123131904 has 144 divisors (see below), whose sum is σ = 382800600. Its totient is φ = 35094528.

The previous prime is 123131891. The next prime is 123131917. The reversal of 123131904 is 409131321.

It is an interprime number because it is at equal distance from previous prime (123131891) and next prime (123131917).

It is a super-2 number, since 2×123131904² = 30322931565330432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 300852 + ... + 301260.

Almost surely, 2^123131904 is an apocalyptic number.

123131904 is a gapful number since it is divisible by the number (14) 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 123131904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (191400300).

123131904 is an abundant number, since it is smaller than the sum of its proper divisors (259668696).

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

123131904 is an equidigital number, since it uses as much as digits as its factorization.

123131904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 448 (or 421 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 123131904 is about 11096.4816045447. The cubic root of 123131904 is about 497.4966931592.

The spelling of 123131904 in words is "one hundred twenty-three million, one hundred thirty-one thousand, nine hundred four".