20864634 has 32 divisors (see below), whose sum is σ = 49766400. Its totient is φ = 5701872.

The previous prime is 20864617. The next prime is 20864647. The reversal of 20864634 is 43646802.

It is a junction number, because it is equal to n+sod(n) for n = 20864595 and 20864604.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9834 + ... + 11765.

It is an arithmetic number, because the mean of its divisors is an integer number (1555200).

Almost surely, 2^20864634 is an apocalyptic number.

20864634 is an abundant number, since it is smaller than the sum of its proper divisors (28901766).

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

20864634 is a wasteful number, since it uses less digits than its factorization.

20864634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21634.

The product of its (nonzero) digits is 27648, while the sum is 33.

The square root of 20864634 is about 4567.7821751918. The cubic root of 20864634 is about 275.2983384843.

The spelling of 20864634 in words is "twenty million, eight hundred sixty-four thousand, six hundred thirty-four".