245156591 has 4 divisors (see below), whose sum is σ = 245285352. Its totient is φ = 245027832.

The previous prime is 245156531. The next prime is 245156603. The reversal of 245156591 is 195651542.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 195651542 = 2 ⋅97825771.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245156591 is a prime.

It is a super-2 number, since 2×245156591² = 120203508221482562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245156531) 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, 61481 + ... + 65346.

It is an arithmetic number, because the mean of its divisors is an integer number (61321338).

Almost surely, 2^245156591 is an apocalyptic number.

245156591 is a deficient number, since it is larger than the sum of its proper divisors (128761).

245156591 is a wasteful number, since it uses less digits than its factorization.

245156591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128760.

The product of its digits is 54000, while the sum is 38.

The square root of 245156591 is about 15657.4771594916. The cubic root of 245156591 is about 625.8657578410.

The spelling of 245156591 in words is "two hundred forty-five million, one hundred fifty-six thousand, five hundred ninety-one".