21799562 has 4 divisors (see below), whose sum is σ = 32699346. Its totient is φ = 10899780.

The previous prime is 21799553. The next prime is 21799567. The reversal of 21799562 is 26599712.

It is a Cunningham number, because it is equal to 4669²+1.

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., 21799561 + 1 = 4669^2 + 1^2 .

It is not an unprimeable number, because it can be changed into a prime (21799567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5449889 + ... + 5449892.

Almost surely, 2^21799562 is an apocalyptic number.

21799562 is a deficient number, since it is larger than the sum of its proper divisors (10899784).

21799562 is a wasteful number, since it uses less digits than its factorization.

21799562 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10899783.

The product of its digits is 68040, while the sum is 41.

The square root of 21799562 is about 4669.0001070893. Note that the first 3 decimals coincide. The cubic root of 21799562 is about 279.3503732211.

The spelling of 21799562 in words is "twenty-one million, seven hundred ninety-nine thousand, five hundred sixty-two".