1251605051 has 2 divisors, whose sum is σ = 1251605052. Its totient is φ = 1251605050.

The previous prime is 1251605039. The next prime is 1251605071. The reversal of 1251605051 is 1505061521.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1251605051 - 2³⁰ = 177863227 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1251605051.

It is not a weakly prime, because it can be changed into another prime (1251605021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625802525 + 625802526.

It is an arithmetic number, because the mean of its divisors is an integer number (625802526).

Almost surely, 2^1251605051 is an apocalyptic number.

1251605051 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251605051 is an equidigital number, since it uses as much as digits as its factorization.

1251605051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1500, while the sum is 26.

The square root of 1251605051 is about 35378.0306263647. The cubic root of 1251605051 is about 1077.6782114889.

Adding to 1251605051 its reverse (1505061521), we get a palindrome (2756666572).

The spelling of 1251605051 in words is "one billion, two hundred fifty-one million, six hundred five thousand, fifty-one".