401864387 has 4 divisors (see below), whose sum is σ = 403132416. Its totient is φ = 400596360.

The previous prime is 401864371. The next prime is 401864413. The reversal of 401864387 is 783468104.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 401864387 - 2⁴ = 401864371 is a prime.

It is a super-2 number, since 2×401864387² = 322989971077771538, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (401864317) 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, 633539 + ... + 634172.

It is an arithmetic number, because the mean of its divisors is an integer number (100783104).

Almost surely, 2^401864387 is an apocalyptic number.

401864387 is a deficient number, since it is larger than the sum of its proper divisors (1268029).

401864387 is a wasteful number, since it uses less digits than its factorization.

401864387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1268028.

The product of its (nonzero) digits is 129024, while the sum is 41.

The square root of 401864387 is about 20046.5554896596. Note that the first 3 decimals coincide. The cubic root of 401864387 is about 737.9492691875.

The spelling of 401864387 in words is "four hundred one million, eight hundred sixty-four thousand, three hundred eighty-seven".