258456661557 has 4 divisors (see below), whose sum is σ = 344608882080. Its totient is φ = 172304441036.

The previous prime is 258456661543. The next prime is 258456661607. The reversal of 258456661557 is 755166654852.

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 258456661557 - 2¹⁵ = 258456628789 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 258456661557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (258456660557) 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, 43076110257 + ... + 43076110262.

It is an arithmetic number, because the mean of its divisors is an integer number (86152220520).

Almost surely, 2^258456661557 is an apocalyptic number.

It is an amenable number.

258456661557 is a deficient number, since it is larger than the sum of its proper divisors (86152220523).

258456661557 is an equidigital number, since it uses as much as digits as its factorization.

258456661557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86152220522.

The product of its digits is 60480000, while the sum is 60.

The spelling of 258456661557 in words is "two hundred fifty-eight billion, four hundred fifty-six million, six hundred sixty-one thousand, five hundred fifty-seven".