21261606545044 has 24 divisors (see below), whose sum is σ = 37634956708608. Its totient is φ = 10509015763200.

The previous prime is 21261606545021. The next prime is 21261606545063. The reversal of 21261606545044 is 44054560616212.

It is a junction number, because it is equal to n+sod(n) for n = 21261606544985 and 21261606545003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31413682 + ... + 32083369.

It is an arithmetic number, because the mean of its divisors is an integer number (1568123196192).

Almost surely, 2^{21261606545044} is an apocalyptic number.

It is an amenable number.

21261606545044 is a deficient number, since it is larger than the sum of its proper divisors (16373350163564).

21261606545044 is a wasteful number, since it uses less digits than its factorization.

21261606545044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63498015 (or 63498013 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 46.

The spelling of 21261606545044 in words is "twenty-one trillion, two hundred sixty-one billion, six hundred six million, five hundred forty-five thousand, forty-four".