21613426437256 has 32 divisors (see below), whose sum is σ = 40558537713600. Its totient is φ = 10797819664320.

The previous prime is 21613426437233. The next prime is 21613426437271. The reversal of 21613426437256 is 65273462431612.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53160150 + ... + 53565178.

It is an arithmetic number, because the mean of its divisors is an integer number (1267454303550).

Almost surely, 2^{21613426437256} is an apocalyptic number.

It is an amenable number.

21613426437256 is a deficient number, since it is larger than the sum of its proper divisors (18945111276344).

21613426437256 is a wasteful number, since it uses less digits than its factorization.

21613426437256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410509 (or 410505 counting only the distinct ones).

The product of its digits is 8709120, while the sum is 52.

Adding to 21613426437256 its reverse (65273462431612), we get a palindrome (86886888868868).

The spelling of 21613426437256 in words is "twenty-one trillion, six hundred thirteen billion, four hundred twenty-six million, four hundred thirty-seven thousand, two hundred fifty-six".