1687121732 has 24 divisors (see below), whose sum is σ = 2975457240. Its totient is φ = 837017600.

The previous prime is 1687121731. The next prime is 1687121747. The reversal of 1687121732 is 2371217861.

It can be written as a sum of positive squares in 4 ways, for example, as 426587716 + 1260534016 = 20654^2 + 35504^2 .

It is not an unprimeable number, because it can be changed into a prime (1687121731) 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, 273482 + ... + 279582.

It is an arithmetic number, because the mean of its divisors is an integer number (123977385).

Almost surely, 2^1687121732 is an apocalyptic number.

It is an amenable number.

1687121732 is a deficient number, since it is larger than the sum of its proper divisors (1288335508).

1687121732 is a wasteful number, since it uses less digits than its factorization.

1687121732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6631 (or 6629 counting only the distinct ones).

The product of its digits is 28224, while the sum is 38.

The square root of 1687121732 is about 41074.5874233692. The cubic root of 1687121732 is about 1190.4618248438.

The spelling of 1687121732 in words is "one billion, six hundred eighty-seven million, one hundred twenty-one thousand, seven hundred thirty-two".