40257731 has 2 divisors, whose sum is σ = 40257732. Its totient is φ = 40257730.

The previous prime is 40257703. The next prime is 40257757. The reversal of 40257731 is 13775204.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 40257731 - 2⁶ = 40257667 is a prime.

It is a super-2 number, since 2×40257731² = 3241369810536722, which contains 22 as substring.

It is equal to p_2448335 and since 40257731 and 2448335 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 40257694 and 40257703.

It is not a weakly prime, because it can be changed into another prime (40257031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20128865 + 20128866.

It is an arithmetic number, because the mean of its divisors is an integer number (20128866).

Almost surely, 2^40257731 is an apocalyptic number.

40257731 is a deficient number, since it is larger than the sum of its proper divisors (1).

40257731 is an equidigital number, since it uses as much as digits as its factorization.

40257731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5880, while the sum is 29.

The square root of 40257731 is about 6344.8980291254. The cubic root of 40257731 is about 342.7281403982.

The spelling of 40257731 in words is "forty million, two hundred fifty-seven thousand, seven hundred thirty-one".