20325661 has 4 divisors (see below), whose sum is σ = 20428000. Its totient is φ = 20223324.

The previous prime is 20325653. The next prime is 20325707. The reversal of 20325661 is 16652302.

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.

It is a cyclic number.

It is not a de Polignac number, because 20325661 - 2³ = 20325653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20325061) 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, 50871 + ... + 51268.

It is an arithmetic number, because the mean of its divisors is an integer number (5107000).

Almost surely, 2^20325661 is an apocalyptic number.

It is an amenable number.

20325661 is a deficient number, since it is larger than the sum of its proper divisors (102339).

20325661 is a wasteful number, since it uses less digits than its factorization.

20325661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102338.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 20325661 is about 4508.3989397568. The cubic root of 20325661 is about 272.9071365422.

Adding to 20325661 its reverse (16652302), we get a palindrome (36977963).

The spelling of 20325661 in words is "twenty million, three hundred twenty-five thousand, six hundred sixty-one".