1249940921 has 2 divisors, whose sum is σ = 1249940922. Its totient is φ = 1249940920.

The previous prime is 1249940903. The next prime is 1249940927. The reversal of 1249940921 is 1290499421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1134679225 + 115261696 = 33685^2 + 10736^2 .

It is a cyclic number.

It is not a de Polignac number, because 1249940921 - 2¹⁴ = 1249924537 is a prime.

It is not a weakly prime, because it can be changed into another prime (1249940927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 624970460 + 624970461.

It is an arithmetic number, because the mean of its divisors is an integer number (624970461).

Almost surely, 2^1249940921 is an apocalyptic number.

It is an amenable number.

1249940921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1249940921 is an equidigital number, since it uses as much as digits as its factorization.

1249940921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 1249940921 is about 35354.5035462245. The cubic root of 1249940921 is about 1077.2003738356.

The spelling of 1249940921 in words is "one billion, two hundred forty-nine million, nine hundred forty thousand, nine hundred twenty-one".