21612036770440 has 16 divisors (see below), whose sum is σ = 48627082733580. Its totient is φ = 8644814708160.

The previous prime is 21612036770417. The next prime is 21612036770449. The reversal of 21612036770440 is 4407763021612.

It can be written as a sum of positive squares in 2 ways, for example, as 18408029849764 + 3204006920676 = 4290458^2 + 1789974^2 .

It is not an unprimeable number, because it can be changed into a prime (21612036770449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270150459591 + ... + 270150459670.

Almost surely, 2^{21612036770440} is an apocalyptic number.

21612036770440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21612036770440 is an abundant number, since it is smaller than the sum of its proper divisors (27015045963140).

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

21612036770440 is a wasteful number, since it uses less digits than its factorization.

21612036770440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540300919272 (or 540300919268 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 43.

The spelling of 21612036770440 in words is "twenty-one trillion, six hundred twelve billion, thirty-six million, seven hundred seventy thousand, four hundred forty".