691298064 has 120 divisors (see below), whose sum is σ = 2124551520. Its totient is φ = 216857088.

The previous prime is 691298063. The next prime is 691298087. The reversal of 691298064 is 460892196.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (691298063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60867 + ... + 71325.

It is an arithmetic number, because the mean of its divisors is an integer number (17704596).

Almost surely, 2^691298064 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691298064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1062275760).

691298064 is an abundant number, since it is smaller than the sum of its proper divisors (1433253456).

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

691298064 is a wasteful number, since it uses less digits than its factorization.

691298064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10499 (or 10481 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 691298064 is about 26292.5476894119. The cubic root of 691298064 is about 884.2093714539.

It can be divided in two parts, 6912 and 98064, that added together give a 4-th power (104976 = 18⁴).

The spelling of 691298064 in words is "six hundred ninety-one million, two hundred ninety-eight thousand, sixty-four".