1531688 has 8 divisors (see below), whose sum is σ = 2871930. Its totient is φ = 765840.

The previous prime is 1531681. The next prime is 1531697. The reversal of 1531688 is 8861351.

It can be written as a sum of positive squares in only one way, i.e., 1044484 + 487204 = 1022^2 + 698^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-3 number, since 3×1531688³ = 10780333202695958016, which contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1531681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95723 + ... + 95738.

2^1531688 is an apocalyptic number.

It is an amenable number.

1531688 is a deficient number, since it is larger than the sum of its proper divisors (1340242).

1531688 is a wasteful number, since it uses less digits than its factorization.

1531688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191467 (or 191463 counting only the distinct ones).

The product of its digits is 5760, while the sum is 32.

The square root of 1531688 is about 1237.6138331483. The cubic root of 1531688 is about 115.2718960285.

The spelling of 1531688 in words is "one million, five hundred thirty-one thousand, six hundred eighty-eight".