20904634 has 8 divisors (see below), whose sum is σ = 31376448. Its totient is φ = 10445820.

The previous prime is 20904619. The next prime is 20904641. The reversal of 20904634 is 43640902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4069 + ... + 7639.

It is an arithmetic number, because the mean of its divisors is an integer number (3922056).

Almost surely, 2^20904634 is an apocalyptic number.

20904634 is a deficient number, since it is larger than the sum of its proper divisors (10471814).

20904634 is a wasteful number, since it uses less digits than its factorization.

20904634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6500.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 20904634 is about 4572.1585711784. The cubic root of 20904634 is about 275.4741527986.

It can be divided in two parts, 2090 and 4634, that added together give a square (6724 = 82²).

The spelling of 20904634 in words is "twenty million, nine hundred four thousand, six hundred thirty-four".