1249505591 has 2 divisors, whose sum is σ = 1249505592. Its totient is φ = 1249505590.

The previous prime is 1249505563. The next prime is 1249505671. The reversal of 1249505591 is 1955059421.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1249505591 - 2²⁶ = 1182396727 is a prime.

It is a super-2 number, since 2×1249505591² = 3122528443880518562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1249505501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 624752795 + 624752796.

It is an arithmetic number, because the mean of its divisors is an integer number (624752796).

Almost surely, 2^1249505591 is an apocalyptic number.

1249505591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1249505591 is an equidigital number, since it uses as much as digits as its factorization.

1249505591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81000, while the sum is 41.

The square root of 1249505591 is about 35348.3463686776. The cubic root of 1249505591 is about 1077.0753033671.

The spelling of 1249505591 in words is "one billion, two hundred forty-nine million, five hundred five thousand, five hundred ninety-one".