21050511345 has 12 divisors (see below), whose sum is σ = 36487553076. Its totient is φ = 11226939360.

The previous prime is 21050511299. The next prime is 21050511347. The reversal of 21050511345 is 54311505012.

21050511345 is a `hidden beast` number, since 2 + 1 + 0 + 505 + 113 + 45 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8747486784 + 12303024561 = 93528^2 + 110919^2 .

It is not a de Polignac number, because 21050511345 - 2²⁰ = 21049462769 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21050511347) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 233894526 + ... + 233894615.

It is an arithmetic number, because the mean of its divisors is an integer number (3040629423).

Almost surely, 2^21050511345 is an apocalyptic number.

It is an amenable number.

21050511345 is a deficient number, since it is larger than the sum of its proper divisors (15437041731).

21050511345 is a wasteful number, since it uses less digits than its factorization.

21050511345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 467789152 (or 467789149 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The spelling of 21050511345 in words is "twenty-one billion, fifty million, five hundred eleven thousand, three hundred forty-five".