1001557649 has 2 divisors, whose sum is σ = 1001557650. Its totient is φ = 1001557648.

The previous prime is 1001557643. The next prime is 1001557691. The reversal of 1001557649 is 9467551001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 810427024 + 191130625 = 28468^2 + 13825^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001557649 - 2⁴ = 1001557633 is a prime.

It is not a weakly prime, because it can be changed into another prime (1001557643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500778824 + 500778825.

It is an arithmetic number, because the mean of its divisors is an integer number (500778825).

Almost surely, 2^1001557649 is an apocalyptic number.

It is an amenable number.

1001557649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001557649 is an equidigital number, since it uses as much as digits as its factorization.

1001557649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 37800, while the sum is 38.

The square root of 1001557649 is about 31647.3956116455. The cubic root of 1001557649 is about 1000.5189469808.

The spelling of 1001557649 in words is "one billion, one million, five hundred fifty-seven thousand, six hundred forty-nine".