20961766 has 16 divisors (see below), whose sum is σ = 37094400. Its totient is φ = 8693640.

The previous prime is 20961761. The next prime is 20961779. The reversal of 20961766 is 66716902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20961761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23716 + ... + 24583.

It is an arithmetic number, because the mean of its divisors is an integer number (2318400).

Almost surely, 2^20961766 is an apocalyptic number.

20961766 is a deficient number, since it is larger than the sum of its proper divisors (16132634).

20961766 is a wasteful number, since it uses less digits than its factorization.

20961766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48339.

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 20961766 is about 4578.4021230119. The cubic root of 20961766 is about 275.7248798773.

The spelling of 20961766 in words is "twenty million, nine hundred sixty-one thousand, seven hundred sixty-six".