20087621 has 4 divisors (see below), whose sum is σ = 20097792. Its totient is φ = 20077452.

The previous prime is 20087603. The next prime is 20087647. The reversal of 20087621 is 12678002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20087621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20087021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1061 + ... + 6426.

It is an arithmetic number, because the mean of its divisors is an integer number (5024448).

Almost surely, 2^20087621 is an apocalyptic number.

It is an amenable number.

20087621 is a deficient number, since it is larger than the sum of its proper divisors (10171).

20087621 is an equidigital number, since it uses as much as digits as its factorization.

20087621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10170.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 20087621 is about 4481.9215745035. The cubic root of 20087621 is about 271.8375841583.

The spelling of 20087621 in words is "twenty million, eighty-seven thousand, six hundred twenty-one".