20902239 has 32 divisors (see below), whose sum is σ = 32739840. Its totient is φ = 13153536.

The previous prime is 20902237. The next prime is 20902241. The reversal of 20902239 is 93220902.

It is an interprime number because it is at equal distance from previous prime (20902237) and next prime (20902241).

It is not a de Polignac number, because 20902239 - 2¹ = 20902237 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20902237) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 60064 + ... + 60410.

It is an arithmetic number, because the mean of its divisors is an integer number (1023120).

Almost surely, 2^20902239 is an apocalyptic number.

20902239 is a deficient number, since it is larger than the sum of its proper divisors (11837601).

20902239 is a wasteful number, since it uses less digits than its factorization.

20902239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476 (or 470 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 20902239 is about 4571.8966523752. The cubic root of 20902239 is about 275.4636322318.

The spelling of 20902239 in words is "twenty million, nine hundred two thousand, two hundred thirty-nine".