1687669497 has 6 divisors (see below), whose sum is σ = 2437744842. Its totient is φ = 1125112992.

The previous prime is 1687669457. The next prime is 1687669507. The reversal of 1687669497 is 7949667861.

1687669497 is a `hidden beast` number, since 1 + 6 + 87 + 6 + 69 + 497 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1598480361 + 89189136 = 39981^2 + 9444^2 .

It is not a de Polignac number, because 1687669497 - 2¹⁸ = 1687407353 is a prime.

It is a super-2 number, since 2×1687669497² = 5696456662208466018, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1687669427) 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, 93759408 + ... + 93759425.

It is an arithmetic number, because the mean of its divisors is an integer number (406290807).

Almost surely, 2^1687669497 is an apocalyptic number.

It is an amenable number.

1687669497 is a deficient number, since it is larger than the sum of its proper divisors (750075345).

1687669497 is a wasteful number, since it uses less digits than its factorization.

1687669497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187518839 (or 187518836 counting only the distinct ones).

The product of its digits is 27433728, while the sum is 63.

The square root of 1687669497 is about 41081.2548128706. The cubic root of 1687669497 is about 1190.5906483403.

The spelling of 1687669497 in words is "one billion, six hundred eighty-seven million, six hundred sixty-nine thousand, four hundred ninety-seven".