20842664 has 32 divisors (see below), whose sum is σ = 40627200. Its totient is φ = 10013760.

The previous prime is 20842631. The next prime is 20842673. The reversal of 20842664 is 46624802.

20842664 = T₃₀₇ + T₃₀₈ + ... + T₅₃₅.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20842664.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56609 + ... + 56975.

It is an arithmetic number, because the mean of its divisors is an integer number (1269600).

Almost surely, 2^20842664 is an apocalyptic number.

It is an amenable number.

20842664 is a deficient number, since it is larger than the sum of its proper divisors (19784536).

20842664 is a wasteful number, since it uses less digits than its factorization.

20842664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633 (or 629 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 20842664 is about 4565.3766547789. The cubic root of 20842664 is about 275.2016768534.

The spelling of 20842664 in words is "twenty million, eight hundred forty-two thousand, six hundred sixty-four".