20451646 has 16 divisors (see below), whose sum is σ = 33895584. Its totient is φ = 9205504.

The previous prime is 20451643. The next prime is 20451647. The reversal of 20451646 is 64615402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20451643) 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 7 ways as a sum of consecutive naturals, for example, 12295 + ... + 13858.

It is an arithmetic number, because the mean of its divisors is an integer number (2118474).

Almost surely, 2^20451646 is an apocalyptic number.

20451646 is a deficient number, since it is larger than the sum of its proper divisors (13443938).

20451646 is a wasteful number, since it uses less digits than its factorization.

20451646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26195.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 20451646 is about 4522.3496105454. The cubic root of 20451646 is about 273.4698310244.

The spelling of 20451646 in words is "twenty million, four hundred fifty-one thousand, six hundred forty-six".