1251504545449 has 2 divisors, whose sum is σ = 1251504545450. Its totient is φ = 1251504545448.

The previous prime is 1251504545407. The next prime is 1251504545471. The reversal of 1251504545449 is 9445454051521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 777791705625 + 473712839824 = 881925^2 + 688268^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1251504545449 is a prime.

It is a super-5 number, since 5×1251504545449⁵ (a number of 62 digits) contains 55555 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (1251504515449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625752272724 + 625752272725.

It is an arithmetic number, because the mean of its divisors is an integer number (625752272725).

Almost surely, 2^{1251504545449} is an apocalyptic number.

It is an amenable number.

1251504545449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251504545449 is an equidigital number, since it uses as much as digits as its factorization.

1251504545449 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880000, while the sum is 49.

The spelling of 1251504545449 in words is "one trillion, two hundred fifty-one billion, five hundred four million, five hundred forty-five thousand, four hundred forty-nine".