21551602017 has 16 divisors (see below), whose sum is σ = 32997669120. Its totient is φ = 12374125200.

The previous prime is 21551601983. The next prime is 21551602043. The reversal of 21551602017 is 71020615512.

It is not a de Polignac number, because 21551602017 - 2¹¹ = 21551599969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21551602087) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17185659 + ... + 17186912.

It is an arithmetic number, because the mean of its divisors is an integer number (2062354320).

Almost surely, 2^21551602017 is an apocalyptic number.

It is an amenable number.

21551602017 is a deficient number, since it is larger than the sum of its proper divisors (11446067103).

21551602017 is a wasteful number, since it uses less digits than its factorization.

21551602017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34372604.

The product of its (nonzero) digits is 4200, while the sum is 30.

The spelling of 21551602017 in words is "twenty-one billion, five hundred fifty-one million, six hundred two thousand, seventeen".