20147657 has 4 divisors (see below), whose sum is σ = 21208080. Its totient is φ = 19087236.

The previous prime is 20147623. The next prime is 20147671. The reversal of 20147657 is 75674102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20147657 - 2¹⁴ = 20131273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20147857) 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, 530183 + ... + 530220.

It is an arithmetic number, because the mean of its divisors is an integer number (5302020).

Almost surely, 2^20147657 is an apocalyptic number.

It is an amenable number.

20147657 is a deficient number, since it is larger than the sum of its proper divisors (1060423).

20147657 is a wasteful number, since it uses less digits than its factorization.

20147657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060422.

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 20147657 is about 4488.6141513835. The cubic root of 20147657 is about 272.1081290466.

The spelling of 20147657 in words is "twenty million, one hundred forty-seven thousand, six hundred fifty-seven".