401823981 has 24 divisors (see below), whose sum is σ = 626019576. Its totient is φ = 246896640.

The previous prime is 401823977. The next prime is 401823997. The reversal of 401823981 is 189328104.

It can be written as a sum of positive squares in 4 ways, for example, as 110439081 + 291384900 = 10509^2 + 17070^2 .

It is not a de Polignac number, because 401823981 - 2² = 401823977 is a prime.

It is a super-2 number, since 2×401823981² = 322925023413376722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401823931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 86781 + ... + 91293.

It is an arithmetic number, because the mean of its divisors is an integer number (26084149).

Almost surely, 2^401823981 is an apocalyptic number.

It is an amenable number.

401823981 is a deficient number, since it is larger than the sum of its proper divisors (224195595).

401823981 is a wasteful number, since it uses less digits than its factorization.

401823981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5293 (or 5290 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 401823981 is about 20045.5476602661. The cubic root of 401823981 is about 737.9245356551.

The spelling of 401823981 in words is "four hundred one million, eight hundred twenty-three thousand, nine hundred eighty-one".