1687289931 has 6 divisors (see below), whose sum is σ = 2437196580. Its totient is φ = 1124859948.

The previous prime is 1687289921. The next prime is 1687289939. The reversal of 1687289931 is 1399827861.

It is not a de Polignac number, because 1687289931 - 2¹⁸ = 1687027787 is a prime.

It is a super-2 number, since 2×1687289931² = 5693894622507969522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1687289939) 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, 93738321 + ... + 93738338.

It is an arithmetic number, because the mean of its divisors is an integer number (406199430).

Almost surely, 2^1687289931 is an apocalyptic number.

1687289931 is a deficient number, since it is larger than the sum of its proper divisors (749906649).

1687289931 is a wasteful number, since it uses less digits than its factorization.

1687289931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187476665 (or 187476662 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 54.

The square root of 1687289931 is about 41076.6348548661. The cubic root of 1687289931 is about 1190.5013848888.

The spelling of 1687289931 in words is "one billion, six hundred eighty-seven million, two hundred eighty-nine thousand, nine hundred thirty-one".