401691187 has 16 divisors (see below), whose sum is σ = 423895680. Its totient is φ = 380442816.

The previous prime is 401691137. The next prime is 401691193. The reversal of 401691187 is 781196104.

It is not a de Polignac number, because 401691187 - 2¹¹ = 401689139 is a prime.

It is a super-2 number, since 2×401691187² = 322711619426937938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (401691107) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5502583 + ... + 5502655.

It is an arithmetic number, because the mean of its divisors is an integer number (26493480).

Almost surely, 2^401691187 is an apocalyptic number.

401691187 is a gapful number since it is divisible by the number (47) formed by its first and last digit.

401691187 is a deficient number, since it is larger than the sum of its proper divisors (22204493).

401691187 is an frugal number, since it uses more digits than its factorization.

401691187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 37.

The square root of 401691187 is about 20042.2350799505. The cubic root of 401691187 is about 737.8432374150.

The spelling of 401691187 in words is "four hundred one million, six hundred ninety-one thousand, one hundred eighty-seven".