20765961 has 12 divisors (see below), whose sum is σ = 30081792. Its totient is φ = 13804056.

The previous prime is 20765957. The next prime is 20765971. The reversal of 20765961 is 16956702.

It is not a de Polignac number, because 20765961 - 2² = 20765957 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20765971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 160 + ... + 6446.

It is an arithmetic number, because the mean of its divisors is an integer number (2506816).

Almost surely, 2^20765961 is an apocalyptic number.

It is an amenable number.

20765961 is a deficient number, since it is larger than the sum of its proper divisors (9315831).

20765961 is a wasteful number, since it uses less digits than its factorization.

20765961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6660 (or 6657 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 20765961 is about 4556.9684001538. The cubic root of 20765961 is about 274.8636723734.

The spelling of 20765961 in words is "twenty million, seven hundred sixty-five thousand, nine hundred sixty-one".