40031557 has 2 divisors, whose sum is σ = 40031558. Its totient is φ = 40031556.

The previous prime is 40031533. The next prime is 40031567. The reversal of 40031557 is 75513004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37625956 + 2405601 = 6134^2 + 1551^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40031557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40031567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20015778 + 20015779.

It is an arithmetic number, because the mean of its divisors is an integer number (20015779).

Almost surely, 2^40031557 is an apocalyptic number.

It is an amenable number.

40031557 is a deficient number, since it is larger than the sum of its proper divisors (1).

40031557 is an equidigital number, since it uses as much as digits as its factorization.

40031557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 40031557 is about 6327.0496283813. The cubic root of 40031557 is about 342.0851018796.

It can be divided in two parts, 400 and 31557, that multiplied together give a triangular number (12622800 = T₅₀₂₄).

The spelling of 40031557 in words is "forty million, thirty-one thousand, five hundred fifty-seven".