20916736 has 20 divisors (see below), whose sum is σ = 41793642. Its totient is φ = 10458112.

The previous prime is 20916713. The next prime is 20916767. The reversal of 20916736 is 63761902.

It can be written as a sum of positive squares in only one way, i.e., 11182336 + 9734400 = 3344^2 + 3120^2 .

It is a plaindrome in base 13.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19915 + ... + 20938.

Almost surely, 2^20916736 is an apocalyptic number.

It is an amenable number.

20916736 is a deficient number, since it is larger than the sum of its proper divisors (20876906).

20916736 is an frugal number, since it uses more digits than its factorization.

20916736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40871 (or 40855 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 20916736 is about 4573.4818246058. The cubic root of 20916736 is about 275.5273012230.

The spelling of 20916736 in words is "twenty million, nine hundred sixteen thousand, seven hundred thirty-six".