1561272151 has 2 divisors, whose sum is σ = 1561272152. Its totient is φ = 1561272150.

The previous prime is 1561272137. The next prime is 1561272157. The reversal of 1561272151 is 1512721651.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1561272151 - 2¹¹ = 1561270103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1561272157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780636075 + 780636076.

It is an arithmetic number, because the mean of its divisors is an integer number (780636076).

Almost surely, 2^1561272151 is an apocalyptic number.

1561272151 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561272151 is an equidigital number, since it uses as much as digits as its factorization.

1561272151 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4200, while the sum is 31.

The square root of 1561272151 is about 39512.9365018597. The cubic root of 1561272151 is about 1160.0931730055.

The spelling of 1561272151 in words is "one billion, five hundred sixty-one million, two hundred seventy-two thousand, one hundred fifty-one".