687748730 has 8 divisors (see below), whose sum is σ = 1237947732. Its totient is φ = 275099488.

The previous prime is 687748727. The next prime is 687748739. The reversal of 687748730 is 37847786.

It can be written as a sum of positive squares in 2 ways, for example, as 620557921 + 67190809 = 24911^2 + 8197^2 .

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

It is a super-2 number, since 2×687748730² = 945996631233225800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (687748739) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34387427 + ... + 34387446.

Almost surely, 2^687748730 is an apocalyptic number.

687748730 is a deficient number, since it is larger than the sum of its proper divisors (550199002).

687748730 is a wasteful number, since it uses less digits than its factorization.

687748730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68774880.

The product of its (nonzero) digits is 1580544, while the sum is 50.

The square root of 687748730 is about 26224.9638703278. The cubic root of 687748730 is about 882.6935077911.

The spelling of 687748730 in words is "six hundred eighty-seven million, seven hundred forty-eight thousand, seven hundred thirty".