21439810265650 has 48 divisors (see below), whose sum is σ = 45576124905600. Its totient is φ = 7350596294400.

The previous prime is 21439810265623. The next prime is 21439810265681. The reversal of 21439810265650 is 5656201893412.

It is a happy number.

It is a super-2 number, since 2×21439810265650² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12660555 + ... + 14253745.

It is an arithmetic number, because the mean of its divisors is an integer number (949502602200).

Almost surely, 2^{21439810265650} is an apocalyptic number.

21439810265650 is an abundant number, since it is smaller than the sum of its proper divisors (24136314639950).

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

21439810265650 is a wasteful number, since it uses less digits than its factorization.

21439810265650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1631659 (or 1631654 counting only the distinct ones).

The product of its (nonzero) digits is 3110400, while the sum is 52.

The spelling of 21439810265650 in words is "twenty-one trillion, four hundred thirty-nine billion, eight hundred ten million, two hundred sixty-five thousand, six hundred fifty".