20531766 has 16 divisors (see below), whose sum is σ = 41526000. Its totient is φ = 6766848.

The previous prime is 20531747. The next prime is 20531783. The reversal of 20531766 is 66713502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18691 + ... + 19758.

It is an arithmetic number, because the mean of its divisors is an integer number (2595375).

Almost surely, 2^20531766 is an apocalyptic number.

20531766 is an abundant number, since it is smaller than the sum of its proper divisors (20994234).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20531766 is a wasteful number, since it uses less digits than its factorization.

20531766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38543.

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 20531766 is about 4531.1991790253. The cubic root of 20531766 is about 273.8264747455.

The spelling of 20531766 in words is "twenty million, five hundred thirty-one thousand, seven hundred sixty-six".