40564391 has 4 divisors (see below), whose sum is σ = 46359312. Its totient is φ = 34769472.

The previous prime is 40564379. The next prime is 40564409. The reversal of 40564391 is 19346504.

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

It is a cyclic number.

It is not a de Polignac number, because 40564391 - 2¹⁴ = 40548007 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 (40564291) 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, 2897450 + ... + 2897463.

It is an arithmetic number, because the mean of its divisors is an integer number (11589828).

Almost surely, 2^40564391 is an apocalyptic number.

40564391 is a deficient number, since it is larger than the sum of its proper divisors (5794921).

40564391 is an equidigital number, since it uses as much as digits as its factorization.

40564391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5794920.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 40564391 is about 6369.0180561842. The cubic root of 40564391 is about 343.5961746568.

The spelling of 40564391 in words is "forty million, five hundred sixty-four thousand, three hundred ninety-one".