1540440457 has 2 divisors, whose sum is σ = 1540440458. Its totient is φ = 1540440456.

The previous prime is 1540440449. The next prime is 1540440497. The reversal of 1540440457 is 7540440451.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1284792336 + 255648121 = 35844^2 + 15989^2 .

It is a cyclic number.

It is not a de Polignac number, because 1540440457 - 2³ = 1540440449 is a prime.

It is not a weakly prime, because it can be changed into another prime (1540440427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 770220228 + 770220229.

It is an arithmetic number, because the mean of its divisors is an integer number (770220229).

Almost surely, 2^1540440457 is an apocalyptic number.

It is an amenable number.

1540440457 is a deficient number, since it is larger than the sum of its proper divisors (1).

1540440457 is an equidigital number, since it uses as much as digits as its factorization.

1540440457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 44800, while the sum is 34.

The square root of 1540440457 is about 39248.4452813102. The cubic root of 1540440457 is about 1154.9104350131.

The spelling of 1540440457 in words is "one billion, five hundred forty million, four hundred forty thousand, four hundred fifty-seven".