21945046951 has 4 divisors (see below), whose sum is σ = 21960151672. Its totient is φ = 21929942232.

The previous prime is 21945046919. The next prime is 21945046957. The reversal of 21945046951 is 15964054912.

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

It is a cyclic number.

It is not a de Polignac number, because 21945046951 - 2⁵ = 21945046919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21945046957) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7550181 + ... + 7553086.

It is an arithmetic number, because the mean of its divisors is an integer number (5490037918).

Almost surely, 2^21945046951 is an apocalyptic number.

21945046951 is a deficient number, since it is larger than the sum of its proper divisors (15104721).

21945046951 is a wasteful number, since it uses less digits than its factorization.

21945046951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15104720.

The product of its (nonzero) digits is 388800, while the sum is 46.

The spelling of 21945046951 in words is "twenty-one billion, nine hundred forty-five million, forty-six thousand, nine hundred fifty-one".