21881962 has 8 divisors (see below), whose sum is σ = 32964516. Its totient is φ = 10893792.

The previous prime is 21881957. The next prime is 21881963. The reversal of 21881962 is 26918812.

It can be written as a sum of positive squares in 2 ways, for example, as 20241001 + 1640961 = 4499^2 + 1281^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21881963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23013 + ... + 23944.

Almost surely, 2^21881962 is an apocalyptic number.

21881962 is a deficient number, since it is larger than the sum of its proper divisors (11082554).

21881962 is a wasteful number, since it uses less digits than its factorization.

21881962 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47192.

The product of its digits is 13824, while the sum is 37.

The square root of 21881962 is about 4677.8159433650. The cubic root of 21881962 is about 279.7019021349.

The spelling of 21881962 in words is "twenty-one million, eight hundred eighty-one thousand, nine hundred sixty-two".