21716156 has 24 divisors (see below), whose sum is σ = 47381376. Its totient is φ = 8460720.

The previous prime is 21716143. The next prime is 21716159. The reversal of 21716156 is 65161712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21716159) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34946 + ... + 35561.

It is an arithmetic number, because the mean of its divisors is an integer number (1974224).

Almost surely, 2^21716156 is an apocalyptic number.

It is an amenable number.

21716156 is an abundant number, since it is smaller than the sum of its proper divisors (25665220).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21716156 is a wasteful number, since it uses less digits than its factorization.

21716156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70529 (or 70527 counting only the distinct ones).

The product of its digits is 2520, while the sum is 29.

The square root of 21716156 is about 4660.0596562705. The cubic root of 21716156 is about 278.9936493033.

Adding to 21716156 its reverse (65161712), we get a palindrome (86877868).

The spelling of 21716156 in words is "twenty-one million, seven hundred sixteen thousand, one hundred fifty-six".