1249021643 has 2 divisors, whose sum is σ = 1249021644. Its totient is φ = 1249021642.

The previous prime is 1249021633. The next prime is 1249021649. The reversal of 1249021643 is 3461209421.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1249021643 - 2¹⁴ = 1249005259 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1249021649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 624510821 + 624510822.

It is an arithmetic number, because the mean of its divisors is an integer number (624510822).

Almost surely, 2^1249021643 is an apocalyptic number.

1249021643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1249021643 is an equidigital number, since it uses as much as digits as its factorization.

1249021643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 1249021643 is about 35341.5002935642. The cubic root of 1249021643 is about 1076.9362308272.

The spelling of 1249021643 in words is "one billion, two hundred forty-nine million, twenty-one thousand, six hundred forty-three".