1687997427 has 8 divisors (see below), whose sum is σ = 2251039440. Its totient is φ = 1125143520.

The previous prime is 1687997417. The next prime is 1687997431. The reversal of 1687997427 is 7247997861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1687997427 - 2¹⁵ = 1687964659 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1687997417) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24552 + ... + 63077.

It is an arithmetic number, because the mean of its divisors is an integer number (281379930).

Almost surely, 2^1687997427 is an apocalyptic number.

1687997427 is a deficient number, since it is larger than the sum of its proper divisors (563042013).

1687997427 is an equidigital number, since it uses as much as digits as its factorization.

1687997427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94053.

The product of its digits is 10668672, while the sum is 60.

The square root of 1687997427 is about 41085.2458554163. The cubic root of 1687997427 is about 1190.6677576532.

The spelling of 1687997427 in words is "one billion, six hundred eighty-seven million, nine hundred ninety-seven thousand, four hundred twenty-seven".