981481631 has 4 divisors (see below), whose sum is σ = 1056980232.
Its totient is φ = 905983032.
The previous prime is 981481609. The next prime is 981481663. The reversal of 981481631 is 136184189.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 136184189 = 53 ⋅2569513.
It is a cyclic number.
It is not a de Polignac number, because 981481631 - 210 = 981480607 is a prime.
It is a super-2 number, since 2×9814816312 = 1926612383980840322, which contains 22 as substring.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (981481601) 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, 37749281 + ... + 37749306.
It is an arithmetic number, because the mean of its divisors is an integer number (264245058).
Almost surely, 2981481631 is an apocalyptic number.
981481631 is a deficient number, since it is larger than the sum of its proper divisors (75498601).
981481631 is a wasteful number, since it uses less digits than its factorization.
981481631 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 75498600.
The product of its digits is 41472, while the sum is 41.
The square root of 981481631 is about 31328.6072304531.
The cubic root of 981481631 is about 993.7887100884.
The spelling of 981481631 in words is "nine hundred eighty-one million, four hundred eighty-one thousand, six hundred thirty-one".