36721391 has 16 divisors (see below), whose sum is σ = 43591680. Its totient is φ = 30270240.

The previous prime is 36721381. The next prime is 36721393. The reversal of 36721391 is 19312763.

It is a happy number.

36721391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 36721391 - 2⁶ = 36721327 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 (36721393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42320 + ... + 43178.

It is an arithmetic number, because the mean of its divisors is an integer number (2724480).

Almost surely, 2^36721391 is an apocalyptic number.

36721391 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

36721391 is a deficient number, since it is larger than the sum of its proper divisors (6870289).

36721391 is a wasteful number, since it uses less digits than its factorization.

36721391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1094.

The product of its digits is 6804, while the sum is 32.

The square root of 36721391 is about 6059.8177365330. The cubic root of 36721391 is about 332.3836923374.

The spelling of 36721391 in words is "thirty-six million, seven hundred twenty-one thousand, three hundred ninety-one".