1249613921 has 2 divisors, whose sum is σ = 1249613922. Its totient is φ = 1249613920.

The previous prime is 1249613903. The next prime is 1249613977. The reversal of 1249613921 is 1293169421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1111222225 + 138391696 = 33335^2 + 11764^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1249613921 is a prime.

It is not a weakly prime, because it can be changed into another prime (1249613221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 624806960 + 624806961.

It is an arithmetic number, because the mean of its divisors is an integer number (624806961).

Almost surely, 2^1249613921 is an apocalyptic number.

It is an amenable number.

1249613921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1249613921 is an equidigital number, since it uses as much as digits as its factorization.

1249613921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 38.

The square root of 1249613921 is about 35349.8786560859. The cubic root of 1249613921 is about 1077.1064293305.

The spelling of 1249613921 in words is "one billion, two hundred forty-nine million, six hundred thirteen thousand, nine hundred twenty-one".