245021657 has 4 divisors (see below), whose sum is σ = 247447716. Its totient is φ = 242595600.

The previous prime is 245021633. The next prime is 245021671. The reversal of 245021657 is 756120542.

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 142181776 + 102839881 = 11924^2 + 10141^2 .

It is a cyclic number.

It is not a de Polignac number, because 245021657 - 2⁶ = 245021593 is a prime.

It is a super-2 number, since 2×245021657² = 120071224798051298, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (245021627) 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, 1212878 + ... + 1213079.

It is an arithmetic number, because the mean of its divisors is an integer number (61861929).

Almost surely, 2^245021657 is an apocalyptic number.

It is an amenable number.

245021657 is a deficient number, since it is larger than the sum of its proper divisors (2426059).

245021657 is a wasteful number, since it uses less digits than its factorization.

245021657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2426058.

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 245021657 is about 15653.1676346994. The cubic root of 245021657 is about 625.7509114233.

The spelling of 245021657 in words is "two hundred forty-five million, twenty-one thousand, six hundred fifty-seven".