1243825949 has 2 divisors, whose sum is σ = 1243825950. Its totient is φ = 1243825948.

The previous prime is 1243825873. The next prime is 1243825951. The reversal of 1243825949 is 9495283421.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 764522500 + 479303449 = 27650^2 + 21893^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1243825949 is a prime.

It is a Sophie Germain prime.

Together with 1243825951, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1243885949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621912974 + 621912975.

It is an arithmetic number, because the mean of its divisors is an integer number (621912975).

Almost surely, 2^1243825949 is an apocalyptic number.

It is an amenable number.

1243825949 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243825949 is an equidigital number, since it uses as much as digits as its factorization.

1243825949 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 47.

The square root of 1243825949 is about 35267.9167090998. The cubic root of 1243825949 is about 1075.4408717009.

The spelling of 1243825949 in words is "one billion, two hundred forty-three million, eight hundred twenty-five thousand, nine hundred forty-nine".