1559681397 has 6 divisors (see below), whose sum is σ = 2252873142. Its totient is φ = 1039787592.

The previous prime is 1559681381. The next prime is 1559681407. The reversal of 1559681397 is 7931869551.

1559681397 is a `hidden beast` number, since 1 + 559 + 6 + 81 + 3 + 9 + 7 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1125334116 + 434347281 = 33546^2 + 20841^2 .

It is not a de Polignac number, because 1559681397 - 2⁴ = 1559681381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1559681317) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 86648958 + ... + 86648975.

It is an arithmetic number, because the mean of its divisors is an integer number (375478857).

Almost surely, 2^1559681397 is an apocalyptic number.

It is an amenable number.

1559681397 is a deficient number, since it is larger than the sum of its proper divisors (693191745).

1559681397 is a wasteful number, since it uses less digits than its factorization.

1559681397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173297939 (or 173297936 counting only the distinct ones).

The product of its digits is 2041200, while the sum is 54.

The square root of 1559681397 is about 39492.8018378033. The cubic root of 1559681397 is about 1159.6990392930.

The spelling of 1559681397 in words is "one billion, five hundred fifty-nine million, six hundred eighty-one thousand, three hundred ninety-seven".