21799534 has 4 divisors (see below), whose sum is σ = 32699304. Its totient is φ = 10899766.

The previous prime is 21799529. The next prime is 21799553. The reversal of 21799534 is 43599712.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5449882 + ... + 5449885.

It is an arithmetic number, because the mean of its divisors is an integer number (8174826).

Almost surely, 2^21799534 is an apocalyptic number.

21799534 is a deficient number, since it is larger than the sum of its proper divisors (10899770).

21799534 is a wasteful number, since it uses less digits than its factorization.

21799534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10899769.

The product of its digits is 68040, while the sum is 40.

The square root of 21799534 is about 4668.9971085877. The cubic root of 21799534 is about 279.3502536191.

It can be divided in two parts, 217 and 99534, that multiplied together give a triangular number (21598878 = T₆₅₇₂).

The spelling of 21799534 in words is "twenty-one million, seven hundred ninety-nine thousand, five hundred thirty-four".