20457666 has 24 divisors (see below), whose sum is σ = 44935020. Its totient is φ = 6725376.

The previous prime is 20457617. The next prime is 20457677. The reversal of 20457666 is 66675402.

It can be written as a sum of positive squares in 2 ways, for example, as 20439441 + 18225 = 4521^2 + 135^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20457666.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6471 + ... + 9098.

Almost surely, 2^20457666 is an apocalyptic number.

20457666 is an abundant number, since it is smaller than the sum of its proper divisors (24477354).

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

20457666 is a wasteful number, since it uses less digits than its factorization.

20457666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15650 (or 15647 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The square root of 20457666 is about 4523.0151447900. The cubic root of 20457666 is about 273.4966605989.

The spelling of 20457666 in words is "twenty million, four hundred fifty-seven thousand, six hundred sixty-six".