21982961954 has 8 divisors (see below), whose sum is σ = 33056674668. Its totient is φ = 10964070400.

The previous prime is 21982961947. The next prime is 21982961963. The reversal of 21982961954 is 45916928912.

It can be written as a sum of positive squares in 2 ways, for example, as 20256974929 + 1725987025 = 142327^2 + 41545^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21982961954² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21982961954.

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, 13704287 + ... + 13705890.

Almost surely, 2^21982961954 is an apocalyptic number.

21982961954 is a deficient number, since it is larger than the sum of its proper divisors (11073712714).

21982961954 is a wasteful number, since it uses less digits than its factorization.

21982961954 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27410580.

The product of its digits is 2799360, while the sum is 56.

The spelling of 21982961954 in words is "twenty-one billion, nine hundred eighty-two million, nine hundred sixty-one thousand, nine hundred fifty-four".