19723451904 has 720 divisors, whose sum is σ = 68533470720. Its totient is φ = 5434490880.

The previous prime is 19723451857. The next prime is 19723451921. The reversal of 19723451904 is 40915432791.

19723451904 is a `hidden beast` number, since 1 + 97 + 23 + 451 + 90 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 19723451904.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 458684907 + ... + 458684949.

It is an arithmetic number, because the mean of its divisors is an integer number (95185376).

Almost surely, 2^19723451904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19723451904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34266735360).

19723451904 is an abundant number, since it is smaller than the sum of its proper divisors (48810018816).

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

19723451904 is a wasteful number, since it uses less digits than its factorization.

19723451904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The spelling of 19723451904 in words is "nineteen billion, seven hundred twenty-three million, four hundred fifty-one thousand, nine hundred four".