4013991 has 12 divisors (see below), whose sum is σ = 5815368. Its totient is φ = 2667984.

The previous prime is 4013987. The next prime is 4013993. The reversal of 4013991 is 1993104.

It is not a de Polignac number, because 4013991 - 2² = 4013987 is a prime.

It is a super-2 number, since 2×4013991² = 32224247496162, which contains 22 as substring.

4013991 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4013993) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5536 + ... + 6218.

It is an arithmetic number, because the mean of its divisors is an integer number (484614).

Almost surely, 2^4013991 is an apocalyptic number.

4013991 is a deficient number, since it is larger than the sum of its proper divisors (1801377).

4013991 is a wasteful number, since it uses less digits than its factorization.

4013991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1342 (or 1339 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 4013991 is about 2003.4946967736. The cubic root of 4013991 is about 158.9249675643.

The spelling of 4013991 in words is "four million, thirteen thousand, nine hundred ninety-one".