123721428204 has 72 divisors (see below), whose sum is σ = 359127612480. Its totient is φ = 35518111200.

The previous prime is 123721428199. The next prime is 123721428209. The reversal of 123721428204 is 402824127321.

123721428204 is a `hidden beast` number, since 1 + 2 + 3 + 7 + 21 + 428 + 204 = 666.

It is an interprime number because it is at equal distance from previous prime (123721428199) and next prime (123721428209).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (123721428209) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8214262 + ... + 8229309.

Almost surely, 2^123721428204 is an apocalyptic number.

It is an amenable number.

123721428204 is an abundant number, since it is smaller than the sum of its proper divisors (235406184276).

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

123721428204 is a wasteful number, since it uses less digits than its factorization.

123721428204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16443611 (or 16443606 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The spelling of 123721428204 in words is "one hundred twenty-three billion, seven hundred twenty-one million, four hundred twenty-eight thousand, two hundred four".