123640512 has 28 divisors (see below), whose sum is σ = 327132696. Its totient is φ = 41213440.

The previous prime is 123640511. The next prime is 123640513. The reversal of 123640512 is 215046321.

It is an interprime number because it is at equal distance from previous prime (123640511) and next prime (123640513).

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

It is not an unprimeable number, because it can be changed into a prime (123640511) 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, 321789 + ... + 322172.

Almost surely, 2^123640512 is an apocalyptic number.

123640512 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

123640512 is an abundant number, since it is smaller than the sum of its proper divisors (203492184).

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

123640512 is an equidigital number, since it uses as much as digits as its factorization.

123640512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 643976 (or 643966 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 123640512 is about 11119.3755220336. The cubic root of 123640512 is about 498.1807379327.

Adding to 123640512 its reverse (215046321), we get a palindrome (338686833).

The spelling of 123640512 in words is "one hundred twenty-three million, six hundred forty thousand, five hundred twelve".