21398712620 has 48 divisors (see below), whose sum is σ = 46616169600. Its totient is φ = 8244986880.

The previous prime is 21398712613. The next prime is 21398712631. The reversal of 21398712620 is 2621789312.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100385 + ... + 229944.

It is an arithmetic number, because the mean of its divisors is an integer number (971170200).

Almost surely, 2^21398712620 is an apocalyptic number.

21398712620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21398712620 is an abundant number, since it is smaller than the sum of its proper divisors (25217456980).

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

21398712620 is a wasteful number, since it uses less digits than its factorization.

21398712620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330458 (or 330456 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 41.

The spelling of 21398712620 in words is "twenty-one billion, three hundred ninety-eight million, seven hundred twelve thousand, six hundred twenty".