20157747 has 8 divisors (see below), whose sum is σ = 26899344. Its totient is φ = 13427328.

The previous prime is 20157743. The next prime is 20157749. The reversal of 20157747 is 74775102.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20157747 - 2² = 20157743 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20157743) 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 7 ways as a sum of consecutive naturals, for example, 3343 + ... + 7175.

It is an arithmetic number, because the mean of its divisors is an integer number (3362418).

Almost surely, 2^20157747 is an apocalyptic number.

20157747 is a deficient number, since it is larger than the sum of its proper divisors (6741597).

20157747 is a wasteful number, since it uses less digits than its factorization.

20157747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5589.

The product of its (nonzero) digits is 13720, while the sum is 33.

The square root of 20157747 is about 4489.7379656278. The cubic root of 20157747 is about 272.1535456232.

The spelling of 20157747 in words is "twenty million, one hundred fifty-seven thousand, seven hundred forty-seven".