1631432881 has 15 divisors (see below), whose sum is σ = 1774806701.
Its totient is φ = 1499637048.
The previous prime is 1631432851. The next prime is 1631432947. The reversal of 1631432881 is 1882341361.
The square root of 1631432881 is 40391.
It is a perfect power (a square), and thus also a powerful number.
1631432881 is a nontrivial binomial coefficient, being equal to C(57122, 2).
It can be written as a sum of positive squares in 2 ways, for example, as 808890481 + 822542400 = 28441^2 + 28680^2
It is not a de Polignac number, because 1631432881 - 213 = 1631424689 is a prime.
It is a super-2 number, since 2×16314328812 = 5323146490415920322, which contains 22 as substring.
It is a Duffinian number.
It is a self number, because there is not a number n which added to its sum of digits gives 1631432881.
It is not an unprimeable number, because it can be changed into a prime (1631432801) by changing a digit.
It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 6825960 + ... + 6826198.
Almost surely, 21631432881 is an apocalyptic number.
1631432881 is the 57121-st triangular number, the 40391-st square number and also the 28561-st hexagonal number.
1631432881 is the 20196-th centered octagonal number and also the 19041-st centered nonagonal number.
It is an amenable number.
1631432881 is a deficient number, since it is larger than the sum of its proper divisors (143373820).
1631432881 is an frugal number, since it uses more digits than its factorization.
1631432881 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 530 (or 252 counting only the distinct ones).
The product of its digits is 27648, while the sum is 37.
The cubic root of 1631432881 is about 1177.2166710873.
The spelling of 1631432881 in words is "one billion, six hundred thirty-one million, four hundred thirty-two thousand, eight hundred eighty-one".