21365560246400 has 48 divisors (see below), whose sum is σ = 52779610554090. Its totient is φ = 8546224097280.

The previous prime is 21365560246357. The next prime is 21365560246441. The reversal of 21365560246400 is 464206556312.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 14920420388416 + 6445139857984 = 3862696^2 + 2538728^2 .

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, 3338365589 + ... + 3338371988.

Almost surely, 2^{21365560246400} is an apocalyptic number.

21365560246400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21365560246400 is an abundant number, since it is smaller than the sum of its proper divisors (31414050307690).

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

21365560246400 is an equidigital number, since it uses as much as digits as its factorization.

21365560246400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6676737601 (or 6676737584 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 44.

The spelling of 21365560246400 in words is "twenty-one trillion, three hundred sixty-five billion, five hundred sixty million, two hundred forty-six thousand, four hundred".