21158170982 has 24 divisors (see below), whose sum is σ = 34929795600. Its totient is φ = 9605213280.

The previous prime is 21158170973. The next prime is 21158171101. The reversal of 21158170982 is 28907185112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 492482 + ... + 533717.

It is an arithmetic number, because the mean of its divisors is an integer number (1455408150).

Almost surely, 2^21158170982 is an apocalyptic number.

21158170982 is a deficient number, since it is larger than the sum of its proper divisors (13771624618).

21158170982 is a wasteful number, since it uses less digits than its factorization.

21158170982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1026288 (or 1026275 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 44.

The spelling of 21158170982 in words is "twenty-one billion, one hundred fifty-eight million, one hundred seventy thousand, nine hundred eighty-two".