1299742891 has 2 divisors, whose sum is σ = 1299742892. Its totient is φ = 1299742890.

The previous prime is 1299742877. The next prime is 1299742931. The reversal of 1299742891 is 1982479921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1299742891 - 2²⁹ = 762871979 is a prime.

It is not a weakly prime, because it can be changed into another prime (1299740891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 649871445 + 649871446.

It is an arithmetic number, because the mean of its divisors is an integer number (649871446).

Almost surely, 2^1299742891 is an apocalyptic number.

1299742891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1299742891 is an equidigital number, since it uses as much as digits as its factorization.

1299742891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653184, while the sum is 52.

The square root of 1299742891 is about 36051.9471180129. The cubic root of 1299742891 is about 1091.3209278216.

The spelling of 1299742891 in words is "one billion, two hundred ninety-nine million, seven hundred forty-two thousand, eight hundred ninety-one".