40405731 has 4 divisors (see below), whose sum is σ = 53874312. Its totient is φ = 26937152.

The previous prime is 40405711. The next prime is 40405747. The reversal of 40405731 is 13750404.

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 40405731 - 2⁹ = 40405219 is a prime.

It is a super-2 number, since 2×40405731² = 3265246195288722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (40405711) 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, 6734286 + ... + 6734291.

It is an arithmetic number, because the mean of its divisors is an integer number (13468578).

Almost surely, 2^40405731 is an apocalyptic number.

40405731 is a deficient number, since it is larger than the sum of its proper divisors (13468581).

40405731 is a wasteful number, since it uses less digits than its factorization.

40405731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13468580.

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 40405731 is about 6356.5502436463. The cubic root of 40405731 is about 343.1476186894.

The spelling of 40405731 in words is "forty million, four hundred five thousand, seven hundred thirty-one".