19804523400 has 144 divisors (see below), whose sum is σ = 68803827300. Its totient is φ = 5099082240.

The previous prime is 19804523399. The next prime is 19804523419. The reversal of 19804523400 is 432540891.

19804523400 is a `hidden beast` number, since 1 + 98 + 0 + 4 + 523 + 40 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 13452752196 + 6351771204 = 115986^2 + 79698^2 .

It is a super-2 number, since 2×19804523400² (a number of 21 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 137499 + ... + 241898.

Almost surely, 2^19804523400 is an apocalyptic number.

19804523400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19804523400 is an abundant number, since it is smaller than the sum of its proper divisors (48999303900).

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

19804523400 is a wasteful number, since it uses less digits than its factorization.

19804523400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379448 (or 379436 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

It can be divided in two parts, 198045 and 23400, that added together give a triangular number (221445 = T₆₆₅).

The spelling of 19804523400 in words is "nineteen billion, eight hundred four million, five hundred twenty-three thousand, four hundred".