2158623967597 has 4 divisors (see below), whose sum is σ = 2158626962140. Its totient is φ = 2158620973056.

The previous prime is 2158623967571. The next prime is 2158623967651. The reversal of 2158623967597 is 7957693268512.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1490123138436 + 668500829161 = 1220706^2 + 817619^2 .

It is a cyclic number.

It is not a de Polignac number, because 2158623967597 - 2³¹ = 2156476483949 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 (2158623967537) 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, 315979 + ... + 2101687.

It is an arithmetic number, because the mean of its divisors is an integer number (539656740535).

Almost surely, 2^{2158623967597} is an apocalyptic number.

It is an amenable number.

2158623967597 is a deficient number, since it is larger than the sum of its proper divisors (2994543).

2158623967597 is a wasteful number, since it uses less digits than its factorization.

2158623967597 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2994542.

The product of its digits is 342921600, while the sum is 70.

The spelling of 2158623967597 in words is "two trillion, one hundred fifty-eight billion, six hundred twenty-three million, nine hundred sixty-seven thousand, five hundred ninety-seven".