40252391 has 4 divisors (see below), whose sum is σ = 40277352. Its totient is φ = 40227432.

The previous prime is 40252339. The next prime is 40252397. The reversal of 40252391 is 19325204.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40252391 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 40252391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40252397) 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, 9881 + ... + 13346.

It is an arithmetic number, because the mean of its divisors is an integer number (10069338).

Almost surely, 2^40252391 is an apocalyptic number.

40252391 is a deficient number, since it is larger than the sum of its proper divisors (24961).

40252391 is a wasteful number, since it uses less digits than its factorization.

40252391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24960.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 40252391 is about 6344.4772046245. The cubic root of 40252391 is about 342.7129859657.

Adding to 40252391 its reverse (19325204), we get a palindrome (59577595).

The spelling of 40252391 in words is "forty million, two hundred fifty-two thousand, three hundred ninety-one".