40216639 has 4 divisors (see below), whose sum is σ = 40303224. Its totient is φ = 40130056.

The previous prime is 40216637. The next prime is 40216681. The reversal of 40216639 is 93661204.

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 40216639 - 2¹ = 40216637 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 40216639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40216633) 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, 42592 + ... + 43525.

It is an arithmetic number, because the mean of its divisors is an integer number (10075806).

Almost surely, 2^40216639 is an apocalyptic number.

40216639 is a deficient number, since it is larger than the sum of its proper divisors (86585).

40216639 is an equidigital number, since it uses as much as digits as its factorization.

40216639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86584.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 40216639 is about 6341.6590100698. The cubic root of 40216639 is about 342.6114905121.

The spelling of 40216639 in words is "forty million, two hundred sixteen thousand, six hundred thirty-nine".