20901087 has 12 divisors (see below), whose sum is σ = 30245904. Its totient is φ = 13908480.

The previous prime is 20901079. The next prime is 20901091. The reversal of 20901087 is 78010902.

It is not a de Polignac number, because 20901087 - 2³ = 20901079 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20901087.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20901047) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3958 + ... + 7580.

It is an arithmetic number, because the mean of its divisors is an integer number (2520492).

Almost surely, 2^20901087 is an apocalyptic number.

20901087 is a deficient number, since it is larger than the sum of its proper divisors (9344817).

20901087 is a wasteful number, since it uses less digits than its factorization.

20901087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4270 (or 4267 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 20901087 is about 4571.7706635395. The cubic root of 20901087 is about 275.4585715310.

Adding to 20901087 its reverse (78010902), we get a palindrome (98911989).

The spelling of 20901087 in words is "twenty million, nine hundred one thousand, eighty-seven".