20807902 has 4 divisors (see below), whose sum is σ = 31211856. Its totient is φ = 10403950.

The previous prime is 20807879. The next prime is 20807903. The reversal of 20807902 is 20970802.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20807903) by changing a digit.

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 as a sum of consecutive naturals, namely, 5201974 + ... + 5201977.

It is an arithmetic number, because the mean of its divisors is an integer number (7802964).

Almost surely, 2^20807902 is an apocalyptic number.

20807902 is a deficient number, since it is larger than the sum of its proper divisors (10403954).

20807902 is a wasteful number, since it uses less digits than its factorization.

20807902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10403953.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 20807902 is about 4561.5679321917. The cubic root of 20807902 is about 275.0485952690.

The spelling of 20807902 in words is "twenty million, eight hundred seven thousand, nine hundred two".