21616220443154 has 4 divisors (see below), whose sum is σ = 32424330664734. Its totient is φ = 10808110221576.

The previous prime is 21616220443117. The next prime is 21616220443183. The reversal of 21616220443154 is 45134402261612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 14106236453929 + 7509983989225 = 3755827^2 + 2740435^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5404055110787 + ... + 5404055110790.

Almost surely, 2^{21616220443154} is an apocalyptic number.

21616220443154 is a deficient number, since it is larger than the sum of its proper divisors (10808110221580).

21616220443154 is a wasteful number, since it uses less digits than its factorization.

21616220443154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10808110221579.

The product of its (nonzero) digits is 276480, while the sum is 41.

The spelling of 21616220443154 in words is "twenty-one trillion, six hundred sixteen billion, two hundred twenty million, four hundred forty-three thousand, one hundred fifty-four".