20807638 has 4 divisors (see below), whose sum is σ = 31211460. Its totient is φ = 10403818.

The previous prime is 20807629. The next prime is 20807687. The reversal of 20807638 is 83670802.

It is a happy number.

It is a semiprime because it is the product of two primes.

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, 5201908 + ... + 5201911.

It is an arithmetic number, because the mean of its divisors is an integer number (7802865).

Almost surely, 2^20807638 is an apocalyptic number.

20807638 is a deficient number, since it is larger than the sum of its proper divisors (10403822).

20807638 is a wasteful number, since it uses less digits than its factorization.

20807638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10403821.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 20807638 is about 4561.5389946815. The cubic root of 20807638 is about 275.0474320388.

The spelling of 20807638 in words is "twenty million, eight hundred seven thousand, six hundred thirty-eight".