20961812 has 24 divisors (see below), whose sum is σ = 38349696. Its totient is φ = 10015488.

The previous prime is 20961803. The next prime is 20961817. The reversal of 20961812 is 21816902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20961817) 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, 6788 + ... + 9380.

It is an arithmetic number, because the mean of its divisors is an integer number (1597904).

Almost surely, 2^20961812 is an apocalyptic number.

It is an amenable number.

20961812 is a deficient number, since it is larger than the sum of its proper divisors (17387884).

20961812 is a wasteful number, since it uses less digits than its factorization.

20961812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2687 (or 2685 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 20961812 is about 4578.4071465959. The cubic root of 20961812 is about 275.7250815673.

The spelling of 20961812 in words is "twenty million, nine hundred sixty-one thousand, eight hundred twelve".