102020657 has 4 divisors (see below), whose sum is σ = 102216996. Its totient is φ = 101824320.

The previous prime is 102020647. The next prime is 102020687. The reversal of 102020657 is 756020201.

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 41165056 + 60855601 = 6416^2 + 7801^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102020657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (102020647) 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, 97388 + ... + 98429.

It is an arithmetic number, because the mean of its divisors is an integer number (25554249).

Almost surely, 2^102020657 is an apocalyptic number.

It is an amenable number.

102020657 is a deficient number, since it is larger than the sum of its proper divisors (196339).

102020657 is an equidigital number, since it uses as much as digits as its factorization.

102020657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196338.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 102020657 is about 10100.5275604792. The cubic root of 102020657 is about 467.2644119792.

Adding to 102020657 its reverse (756020201), we get a palindrome (858040858).

The spelling of 102020657 in words is "one hundred two million, twenty thousand, six hundred fifty-seven".