20390949 has 12 divisors (see below), whose sum is σ = 30734496. Its totient is φ = 13002792.

The previous prime is 20390947. The next prime is 20391037. The reversal of 20390949 is 94909302.

It is not a de Polignac number, because 20390949 - 2¹ = 20390947 is a prime.

It is a super-2 number, since 2×20390949² = 831581602241202, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20390941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 49047 + ... + 49460.

It is an arithmetic number, because the mean of its divisors is an integer number (2561208).

Almost surely, 2^20390949 is an apocalyptic number.

It is an amenable number.

20390949 is a deficient number, since it is larger than the sum of its proper divisors (10343547).

20390949 is a wasteful number, since it uses less digits than its factorization.

20390949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98536 (or 98533 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 20390949 is about 4515.6338425519. The cubic root of 20390949 is about 273.1990256613.

The spelling of 20390949 in words is "twenty million, three hundred ninety thousand, nine hundred forty-nine".