20747057 has 4 divisors (see below), whose sum is σ = 20980260. Its totient is φ = 20513856.

The previous prime is 20747053. The next prime is 20747063. The reversal of 20747057 is 75074702.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6677056 + 14070001 = 2584^2 + 3751^2 .

It is a cyclic number.

It is not a de Polignac number, because 20747057 - 2² = 20747053 is a prime.

It is a super-2 number, since 2×20747057² = 860880748322498, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20747053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116468 + ... + 116645.

It is an arithmetic number, because the mean of its divisors is an integer number (5245065).

Almost surely, 2^20747057 is an apocalyptic number.

It is an amenable number.

20747057 is a deficient number, since it is larger than the sum of its proper divisors (233203).

20747057 is an equidigital number, since it uses as much as digits as its factorization.

20747057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233202.

The product of its (nonzero) digits is 13720, while the sum is 32.

The square root of 20747057 is about 4554.8937419000. The cubic root of 20747057 is about 274.7802409610.

The spelling of 20747057 in words is "twenty million, seven hundred forty-seven thousand, fifty-seven".