20390965 has 16 divisors (see below), whose sum is σ = 28038528. Its totient is φ = 13945536.

The previous prime is 20390947. The next prime is 20391037. The reversal of 20390965 is 56909302.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20390965 - 2¹⁹ = 19866677 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20390965.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23479 + ... + 24331.

It is an arithmetic number, because the mean of its divisors is an integer number (1752408).

Almost surely, 2^20390965 is an apocalyptic number.

It is an amenable number.

20390965 is a deficient number, since it is larger than the sum of its proper divisors (7647563).

20390965 is an equidigital number, since it uses as much as digits as its factorization.

20390965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1548.

The product of its (nonzero) digits is 14580, while the sum is 34.

The square root of 20390965 is about 4515.6356141744. The cubic root of 20390965 is about 273.1990971176.

The spelling of 20390965 in words is "twenty million, three hundred ninety thousand, nine hundred sixty-five".