21266154306442 has 16 divisors (see below), whose sum is σ = 32095212683040. Its totient is φ = 10567751218992.

The previous prime is 21266154306391. The next prime is 21266154306497. The reversal of 21266154306442 is 24460345166212.

It is a junction number, because it is equal to n+sod(n) for n = 21266154306392 and 21266154306401.

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, 51489109 + ... + 51900487.

It is an arithmetic number, because the mean of its divisors is an integer number (2005950792690).

Almost surely, 2^{21266154306442} is an apocalyptic number.

21266154306442 is a deficient number, since it is larger than the sum of its proper divisors (10829058376598).

21266154306442 is a wasteful number, since it uses less digits than its factorization.

21266154306442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570117.

The product of its (nonzero) digits is 1658880, while the sum is 46.

It can be divided in two parts, 21266154 and 306442, that added together give a triangular number (21572596 = T₆₅₆₈).

The spelling of 21266154306442 in words is "twenty-one trillion, two hundred sixty-six billion, one hundred fifty-four million, three hundred six thousand, four hundred forty-two".