2157658249808 has 10 divisors (see below), whose sum is σ = 4180462859034. Its totient is φ = 1078829124896.

The previous prime is 2157658249801. The next prime is 2157658249829. The reversal of 2157658249808 is 8089428567512.

It can be written as a sum of positive squares in only one way, i.e., 1319723059264 + 837935190544 = 1148792^2 + 915388^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157658249801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67426820291 + ... + 67426820322.

Almost surely, 2^{2157658249808} is an apocalyptic number.

It is an amenable number.

2157658249808 is a deficient number, since it is larger than the sum of its proper divisors (2022804609226).

2157658249808 is a wasteful number, since it uses less digits than its factorization.

2157658249808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134853640621 (or 134853640615 counting only the distinct ones).

The product of its (nonzero) digits is 77414400, while the sum is 65.

The spelling of 2157658249808 in words is "two trillion, one hundred fifty-seven billion, six hundred fifty-eight million, two hundred forty-nine thousand, eight hundred eight".