36143991 has 12 divisors (see below), whose sum is σ = 56224168. Its totient is φ = 22242384.

The previous prime is 36143981. The next prime is 36143993. The reversal of 36143991 is 19934163.

36143991 is a `hidden beast` number, since 3 + 614 + 39 + 9 + 1 = 666.

It is not a de Polignac number, because 36143991 - 2¹¹ = 36141943 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (36143993) 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, 154345 + ... + 154578.

Almost surely, 2^36143991 is an apocalyptic number.

36143991 is a deficient number, since it is larger than the sum of its proper divisors (20080177).

36143991 is a wasteful number, since it uses less digits than its factorization.

36143991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308942 (or 308939 counting only the distinct ones).

The product of its digits is 17496, while the sum is 36.

The square root of 36143991 is about 6011.9872754356. The cubic root of 36143991 is about 330.6323687048.

The spelling of 36143991 in words is "thirty-six million, one hundred forty-three thousand, nine hundred ninety-one".