21183020091 has 6 divisors (see below), whose sum is σ = 30597695700. Its totient is φ = 14122013388.

The previous prime is 21183020087. The next prime is 21183020123. The reversal of 21183020091 is 19002038112.

It is not a de Polignac number, because 21183020091 - 2² = 21183020087 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21183020041) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1176834441 + ... + 1176834458.

It is an arithmetic number, because the mean of its divisors is an integer number (5099615950).

Almost surely, 2^21183020091 is an apocalyptic number.

21183020091 is a deficient number, since it is larger than the sum of its proper divisors (9414675609).

21183020091 is a wasteful number, since it uses less digits than its factorization.

21183020091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2353668905 (or 2353668902 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The spelling of 21183020091 in words is "twenty-one billion, one hundred eighty-three million, twenty thousand, ninety-one".