21234657800 has 24 divisors (see below), whose sum is σ = 49370579850. Its totient is φ = 8493863040.

The previous prime is 21234657781. The next prime is 21234657817. The reversal of 21234657800 is 875643212.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 9164998756 + 12069659044 = 95734^2 + 109862^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 53086445 + ... + 53086844.

Almost surely, 2^21234657800 is an apocalyptic number.

21234657800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21234657800 is an abundant number, since it is smaller than the sum of its proper divisors (28135922050).

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

21234657800 is a wasteful number, since it uses less digits than its factorization.

21234657800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106173305 (or 106173296 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 38.

The spelling of 21234657800 in words is "twenty-one billion, two hundred thirty-four million, six hundred fifty-seven thousand, eight hundred".