1688047740 has 72 divisors (see below), whose sum is σ = 5343051168. Its totient is φ = 430573440.

The previous prime is 1688047733. The next prime is 1688047769. The reversal of 1688047740 is 477408861.

1688047740 is a `hidden beast` number, since 1 + 68 + 80 + 477 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 199731 + ... + 208010.

It is an arithmetic number, because the mean of its divisors is an integer number (74209044).

Almost surely, 2^1688047740 is an apocalyptic number.

1688047740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1688047740 is an abundant number, since it is smaller than the sum of its proper divisors (3655003428).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1688047740 is a wasteful number, since it uses less digits than its factorization.

1688047740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407779 (or 407774 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 45.

The square root of 1688047740 is about 41085.8581509502. The cubic root of 1688047740 is about 1190.6795873458.

It can be divided in two parts, 16880 and 47740, that added together give a triangular number (64620 = T₃₅₉).

The spelling of 1688047740 in words is "one billion, six hundred eighty-eight million, forty-seven thousand, seven hundred forty".