2151546566557 has 4 divisors (see below), whose sum is σ = 2151551377756. Its totient is φ = 2151541755360.

The previous prime is 2151546566531. The next prime is 2151546566567. The reversal of 2151546566557 is 7556656451512.

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 620422453561 + 1531124112996 = 787669^2 + 1237386^2 .

It is a cyclic number.

It is not a de Polignac number, because 2151546566557 - 2³⁵ = 2117186828189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2151546566527) 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, 1657194 + ... + 2655067.

It is an arithmetic number, because the mean of its divisors is an integer number (537887844439).

Almost surely, 2^{2151546566557} is an apocalyptic number.

It is an amenable number.

2151546566557 is a deficient number, since it is larger than the sum of its proper divisors (4811199).

2151546566557 is an equidigital number, since it uses as much as digits as its factorization.

2151546566557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4811198.

The product of its digits is 37800000, while the sum is 58.

The spelling of 2151546566557 in words is "two trillion, one hundred fifty-one billion, five hundred forty-six million, five hundred sixty-six thousand, five hundred fifty-seven".