1551561113 has 2 divisors, whose sum is σ = 1551561114. Its totient is φ = 1551561112.

The previous prime is 1551561107. The next prime is 1551561197. The reversal of 1551561113 is 3111651551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1382872969 + 168688144 = 37187^2 + 12988^2 .

It is a cyclic number.

It is not a de Polignac number, because 1551561113 - 2¹⁶ = 1551495577 is a prime.

It is not a weakly prime, because it can be changed into another prime (1551561313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775780556 + 775780557.

It is an arithmetic number, because the mean of its divisors is an integer number (775780557).

Almost surely, 2^1551561113 is an apocalyptic number.

It is an amenable number.

1551561113 is a deficient number, since it is larger than the sum of its proper divisors (1).

1551561113 is an equidigital number, since it uses as much as digits as its factorization.

1551561113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2250, while the sum is 29.

The square root of 1551561113 is about 39389.8605354221. The cubic root of 1551561113 is about 1157.6829275490.

The spelling of 1551561113 in words is "one billion, five hundred fifty-one million, five hundred sixty-one thousand, one hundred thirteen".