1267495921 has 2 divisors, whose sum is σ = 1267495922. Its totient is φ = 1267495920.

The previous prime is 1267495913. The next prime is 1267495949. The reversal of 1267495921 is 1295947621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1213546896 + 53949025 = 34836^2 + 7345^2 .

It is a cyclic number.

It is not a de Polignac number, because 1267495921 - 2³ = 1267495913 is a prime.

It is not a weakly prime, because it can be changed into another prime (1267495951) 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, 633747960 + 633747961.

It is an arithmetic number, because the mean of its divisors is an integer number (633747961).

Almost surely, 2^1267495921 is an apocalyptic number.

It is an amenable number.

1267495921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1267495921 is an equidigital number, since it uses as much as digits as its factorization.

1267495921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 272160, while the sum is 46.

The square root of 1267495921 is about 35601.9089516279. The cubic root of 1267495921 is about 1082.2199197527.

The spelling of 1267495921 in words is "one billion, two hundred sixty-seven million, four hundred ninety-five thousand, nine hundred twenty-one".