36638391 has 4 divisors (see below), whose sum is σ = 48851192. Its totient is φ = 24425592.

The previous prime is 36638389. The next prime is 36638401. The reversal of 36638391 is 19383663.

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

It is not a de Polignac number, because 36638391 - 2¹ = 36638389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (36638891) 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, 6106396 + ... + 6106401.

It is an arithmetic number, because the mean of its divisors is an integer number (12212798).

Almost surely, 2^36638391 is an apocalyptic number.

36638391 is a deficient number, since it is larger than the sum of its proper divisors (12212801).

36638391 is a wasteful number, since it uses less digits than its factorization.

36638391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12212800.

The product of its digits is 69984, while the sum is 39.

The square root of 36638391 is about 6052.9654715685. The cubic root of 36638391 is about 332.1330785751.

The spelling of 36638391 in words is "thirty-six million, six hundred thirty-eight thousand, three hundred ninety-one".