1361611557 has 12 divisors (see below), whose sum is σ = 1974087180. Its totient is φ = 904364928.

The previous prime is 1361611547. The next prime is 1361611591. The reversal of 1361611557 is 7551161631.

1361611557 is a `hidden beast` number, since 1 + 36 + 1 + 611 + 5 + 5 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 535968801 + 825642756 = 23151^2 + 28734^2 .

It is not a de Polignac number, because 1361611557 - 2⁸ = 1361611301 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361611547) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 278788 + ... + 283629.

It is an arithmetic number, because the mean of its divisors is an integer number (164507265).

Almost surely, 2^1361611557 is an apocalyptic number.

It is an amenable number.

1361611557 is a deficient number, since it is larger than the sum of its proper divisors (612475623).

1361611557 is a wasteful number, since it uses less digits than its factorization.

1361611557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 562692 (or 562689 counting only the distinct ones).

The product of its digits is 18900, while the sum is 36.

The square root of 1361611557 is about 36900.0210975549. The cubic root of 1361611557 is about 1108.3690999343.

The spelling of 1361611557 in words is "one billion, three hundred sixty-one million, six hundred eleven thousand, five hundred fifty-seven".