465991981 has 72 divisors (see below), whose sum is σ = 647205120. Its totient is φ = 327914496.

The previous prime is 465991979. The next prime is 465992027. The reversal of 465991981 is 189199564.

It is a happy number.

It is not a de Polignac number, because 465991981 - 2¹ = 465991979 is a prime.

It is a super-2 number, since 2×465991981² = 434297052712608722, 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 (465991081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 9914700 + ... + 9914746.

It is an arithmetic number, because the mean of its divisors is an integer number (8988960).

Almost surely, 2^465991981 is an apocalyptic number.

It is an amenable number.

465991981 is a deficient number, since it is larger than the sum of its proper divisors (181213139).

465991981 is a wasteful number, since it uses less digits than its factorization.

465991981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143 (or 113 counting only the distinct ones).

The product of its digits is 699840, while the sum is 52.

The square root of 465991981 is about 21586.8474076230. The cubic root of 465991981 is about 775.2816075469.

The spelling of 465991981 in words is "four hundred sixty-five million, nine hundred ninety-one thousand, nine hundred eighty-one".