688181429 has 8 divisors (see below), whose sum is σ = 741467832. Its totient is φ = 634944960.

The previous prime is 688181423. The next prime is 688181441. The reversal of 688181429 is 924181886.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 39715204 + 648466225 = 6302^2 + 25465^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-688181429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688181423) 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, 19127 + ... + 41739.

It is an arithmetic number, because the mean of its divisors is an integer number (92683479).

Almost surely, 2^688181429 is an apocalyptic number.

It is an amenable number.

688181429 is a deficient number, since it is larger than the sum of its proper divisors (53286403).

688181429 is a wasteful number, since it uses less digits than its factorization.

688181429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24967.

The product of its digits is 221184, while the sum is 47.

The square root of 688181429 is about 26233.2123271246. The cubic root of 688181429 is about 882.8785853297.

The spelling of 688181429 in words is "six hundred eighty-eight million, one hundred eighty-one thousand, four hundred twenty-nine".