1219890449 has 2 divisors, whose sum is σ = 1219890450. Its totient is φ = 1219890448.

The previous prime is 1219890443. The next prime is 1219890457. The reversal of 1219890449 is 9440989121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 866713600 + 353176849 = 29440^2 + 18793^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1219890449 is a prime.

It is a super-2 number, since 2×1219890449² = 2976265415122843202, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1219890443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609945224 + 609945225.

It is an arithmetic number, because the mean of its divisors is an integer number (609945225).

Almost surely, 2^1219890449 is an apocalyptic number.

It is an amenable number.

1219890449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1219890449 is an equidigital number, since it uses as much as digits as its factorization.

1219890449 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 47.

The square root of 1219890449 is about 34926.9301399364. The cubic root of 1219890449 is about 1068.4977459947.

The spelling of 1219890449 in words is "one billion, two hundred nineteen million, eight hundred ninety thousand, four hundred forty-nine".