21986502955 has 4 divisors (see below), whose sum is σ = 26383803552. Its totient is φ = 17589202360.

The previous prime is 21986502949. The next prime is 21986502977. The reversal of 21986502955 is 55920568912.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21986502955 - 2³ = 21986502947 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2198650291 + ... + 2198650300.

It is an arithmetic number, because the mean of its divisors is an integer number (6595950888).

Almost surely, 2^21986502955 is an apocalyptic number.

21986502955 is a deficient number, since it is larger than the sum of its proper divisors (4397300597).

21986502955 is an equidigital number, since it uses as much as digits as its factorization.

21986502955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4397300596.

The product of its (nonzero) digits is 1944000, while the sum is 52.

The spelling of 21986502955 in words is "twenty-one billion, nine hundred eighty-six million, five hundred two thousand, nine hundred fifty-five".