40685731 has 2 divisors, whose sum is σ = 40685732. Its totient is φ = 40685730.

The previous prime is 40685713. The next prime is 40685737. The reversal of 40685731 is 13758604.

Together with previous prime (40685713) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 40685731 - 2⁵ = 40685699 is a prime.

It is a super-2 number, since 2×40685731² = 3310657414008722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (40685737) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20342865 + 20342866.

It is an arithmetic number, because the mean of its divisors is an integer number (20342866).

Almost surely, 2^40685731 is an apocalyptic number.

40685731 is a deficient number, since it is larger than the sum of its proper divisors (1).

40685731 is an equidigital number, since it uses as much as digits as its factorization.

40685731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 40685731 is about 6378.5367444266. The cubic root of 40685731 is about 343.9384326223.

The spelling of 40685731 in words is "forty million, six hundred eighty-five thousand, seven hundred thirty-one".