20406465 has 32 divisors (see below), whose sum is σ = 36806400. Its totient is φ = 10725120.

The previous prime is 20406461. The next prime is 20406521. The reversal of 20406465 is 56460402.

It is a happy number.

It is not a de Polignac number, because 20406465 - 2² = 20406461 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20406461) 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 31 ways as a sum of consecutive naturals, for example, 8521 + ... + 10649.

It is an arithmetic number, because the mean of its divisors is an integer number (1150200).

Almost surely, 2^20406465 is an apocalyptic number.

It is an amenable number.

20406465 is a deficient number, since it is larger than the sum of its proper divisors (16399935).

20406465 is a wasteful number, since it uses less digits than its factorization.

20406465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2214 (or 2208 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 20406465 is about 4517.3515470904. The cubic root of 20406465 is about 273.2683028254.

Adding to 20406465 its reverse (56460402), we get a palindrome (76866867).

The spelling of 20406465 in words is "twenty million, four hundred six thousand, four hundred sixty-five".