40657650581 has 2 divisors, whose sum is σ = 40657650582. Its totient is φ = 40657650580.

The previous prime is 40657650571. The next prime is 40657650613. The reversal of 40657650581 is 18505675604.

40657650581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40656269956 + 1380625 = 201634^2 + 1175^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40657650581 is a prime.

It is a super-2 number, since 2×40657650581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40657650571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20328825290 + 20328825291.

It is an arithmetic number, because the mean of its divisors is an integer number (20328825291).

Almost surely, 2^40657650581 is an apocalyptic number.

It is an amenable number.

40657650581 is a deficient number, since it is larger than the sum of its proper divisors (1).

40657650581 is an equidigital number, since it uses as much as digits as its factorization.

40657650581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008000, while the sum is 47.

The spelling of 40657650581 in words is "forty billion, six hundred fifty-seven million, six hundred fifty thousand, five hundred eighty-one".