401724981 has 24 divisors (see below), whose sum is σ = 692317440. Its totient is φ = 229556376.

The previous prime is 401724971. The next prime is 401724989. The reversal of 401724981 is 189427104.

401724981 is a `hidden beast` number, since 401 + 7 + 249 + 8 + 1 = 666.

It is not a de Polignac number, because 401724981 - 2¹¹ = 401722933 is a prime.

It is a super-2 number, since 2×401724981² = 322765920718900722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401724989) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 150501 + ... + 153146.

It is an arithmetic number, because the mean of its divisors is an integer number (28846560).

Almost surely, 2^401724981 is an apocalyptic number.

It is an amenable number.

401724981 is a deficient number, since it is larger than the sum of its proper divisors (290592459).

401724981 is a wasteful number, since it uses less digits than its factorization.

401724981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303670 (or 303657 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 401724981 is about 20043.0781318639. The cubic root of 401724981 is about 737.8639282474.

The spelling of 401724981 in words is "four hundred one million, seven hundred twenty-four thousand, nine hundred eighty-one".