21431786090400 has 2592 divisors, whose sum is σ = 98161076664000. Its totient is φ = 4487112806400.

The previous prime is 21431786090321. The next prime is 21431786090413. The reversal of 21431786090400 is 409068713412.

21431786090400 is a `hidden beast` number, since 2 + 1 + 4 + 31 + 7 + 8 + 609 + 0 + 4 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 19325325046 + ... + 19325326154.

It is an arithmetic number, because the mean of its divisors is an integer number (37870785750).

Almost surely, 2^{21431786090400} is an apocalyptic number.

21431786090400 is a gapful number since it is divisible by the number (20) 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 21431786090400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49080538332000).

21431786090400 is an abundant number, since it is smaller than the sum of its proper divisors (76729290573600).

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

21431786090400 is a wasteful number, since it uses less digits than its factorization.

21431786090400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1233 (or 1176 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 21431786090400 in words is "twenty-one trillion, four hundred thirty-one billion, seven hundred eighty-six million, ninety thousand, four hundred".