21727534 has 4 divisors (see below), whose sum is σ = 32591304. Its totient is φ = 10863766.

The previous prime is 21727493. The next prime is 21727543. The reversal of 21727534 is 43572712.

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

It is a junction number, because it is equal to n+sod(n) for n = 21727496 and 21727505.

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, 5431882 + ... + 5431885.

It is an arithmetic number, because the mean of its divisors is an integer number (8147826).

Almost surely, 2^21727534 is an apocalyptic number.

21727534 is a deficient number, since it is larger than the sum of its proper divisors (10863770).

21727534 is a wasteful number, since it uses less digits than its factorization.

21727534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10863769.

The product of its digits is 11760, while the sum is 31.

The square root of 21727534 is about 4661.2802962276. The cubic root of 21727534 is about 279.0423662662.

The spelling of 21727534 in words is "twenty-one million, seven hundred twenty-seven thousand, five hundred thirty-four".