20904502 has 4 divisors (see below), whose sum is σ = 31356756. Its totient is φ = 10452250.

The previous prime is 20904497. The next prime is 20904511. The reversal of 20904502 is 20540902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 20540902 = 2 ⋅10270451.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5226124 + ... + 5226127.

It is an arithmetic number, because the mean of its divisors is an integer number (7839189).

Almost surely, 2^20904502 is an apocalyptic number.

20904502 is a deficient number, since it is larger than the sum of its proper divisors (10452254).

20904502 is a wasteful number, since it uses less digits than its factorization.

20904502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10452253.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 20904502 is about 4572.1441359607. The cubic root of 20904502 is about 275.4735729803.

The spelling of 20904502 in words is "twenty million, nine hundred four thousand, five hundred two".