1540249639 has 2 divisors, whose sum is σ = 1540249640. Its totient is φ = 1540249638.

The previous prime is 1540249631. The next prime is 1540249673. The reversal of 1540249639 is 9369420451.

It is a weak prime.

It is an emirp because it is prime and its reverse (9369420451) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1540249639 - 2³ = 1540249631 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1540249595 and 1540249604.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1540249631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 770124819 + 770124820.

It is an arithmetic number, because the mean of its divisors is an integer number (770124820).

Almost surely, 2^1540249639 is an apocalyptic number.

1540249639 is a deficient number, since it is larger than the sum of its proper divisors (1).

1540249639 is an equidigital number, since it uses as much as digits as its factorization.

1540249639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 1540249639 is about 39246.0143071879. The cubic root of 1540249639 is about 1154.8627458822.

The spelling of 1540249639 in words is "one billion, five hundred forty million, two hundred forty-nine thousand, six hundred thirty-nine".