20634736 has 40 divisors (see below), whose sum is σ = 42787440. Its totient is φ = 9606144.

The previous prime is 20634709. The next prime is 20634743. The reversal of 20634736 is 63743602.

20634736 = 76² + 77² + ... + 396².

It is a junction number, because it is equal to n+sod(n) for n = 20634698 and 20634707.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28750 + ... + 29458.

It is an arithmetic number, because the mean of its divisors is an integer number (1069686).

Almost surely, 2^20634736 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20634736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21393720).

20634736 is an abundant number, since it is smaller than the sum of its proper divisors (22152704).

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

20634736 is a wasteful number, since it uses less digits than its factorization.

20634736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841 (or 835 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 31.

The square root of 20634736 is about 4542.5473030008. The cubic root of 20634736 is about 274.2834724106.

The spelling of 20634736 in words is "twenty million, six hundred thirty-four thousand, seven hundred thirty-six".