21221546122456 has 8 divisors (see below), whose sum is σ = 39790398979620. Its totient is φ = 10610773061224.

The previous prime is 21221546122429. The next prime is 21221546122477. The reversal of 21221546122456 is 65422164512212.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1326346632646 + ... + 1326346632661.

Almost surely, 2^{21221546122456} is an apocalyptic number.

It is an amenable number.

21221546122456 is a deficient number, since it is larger than the sum of its proper divisors (18568852857164).

21221546122456 is a wasteful number, since it uses less digits than its factorization.

21221546122456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2652693265313 (or 2652693265309 counting only the distinct ones).

The product of its digits is 460800, while the sum is 43.

The spelling of 21221546122456 in words is "twenty-one trillion, two hundred twenty-one billion, five hundred forty-six million, one hundred twenty-two thousand, four hundred fifty-six".