21965952194 has 4 divisors (see below), whose sum is σ = 32948928294. Its totient is φ = 10982976096.

The previous prime is 21965952163. The next prime is 21965952221. The reversal of 21965952194 is 49125956912.

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

It can be written as a sum of positive squares in only one way, i.e., 20617226569 + 1348725625 = 143587^2 + 36725^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5491488047 + ... + 5491488050.

Almost surely, 2^21965952194 is an apocalyptic number.

21965952194 is a deficient number, since it is larger than the sum of its proper divisors (10982976100).

21965952194 is a wasteful number, since it uses less digits than its factorization.

21965952194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10982976099.

The product of its digits is 1749600, while the sum is 53.

The spelling of 21965952194 in words is "twenty-one billion, nine hundred sixty-five million, nine hundred fifty-two thousand, one hundred ninety-four".