2157546761881 has 9 divisors (see below), whose sum is σ = 2509811255199. Its totient is φ = 1849316982744.

The previous prime is 2157546761863. The next prime is 2157546761893. The reversal of 2157546761881 is 1881676457512.

The square root of 2157546761881 is 1468859.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2007223065225 + 150323696656 = 1416765^2 + 387716^2 .

It is not a de Polignac number, because 2157546761881 - 2⁷ = 2157546761753 is a prime.

It is a super-2 number, since 2×2157546761881² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2157546761081) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 10177095 + ... + 10386931.

Almost surely, 2^{2157546761881} is an apocalyptic number.

2157546761881 is the 1468859-th square number.

2157546761881 is the 734430-th centered octagonal number.

It is an amenable number.

2157546761881 is a deficient number, since it is larger than the sum of its proper divisors (352264493318).

2157546761881 is an frugal number, since it uses more digits than its factorization.

2157546761881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419688 (or 209844 counting only the distinct ones).

The product of its digits is 22579200, while the sum is 61.

The spelling of 2157546761881 in words is "two trillion, one hundred fifty-seven billion, five hundred forty-six million, seven hundred sixty-one thousand, eight hundred eighty-one".