691254889 has 8 divisors (see below), whose sum is σ = 748733832. Its totient is φ = 634391040.

The previous prime is 691254881. The next prime is 691254899. The reversal of 691254889 is 988452196.

It can be written as a sum of positive squares in 4 ways, for example, as 12131289 + 679123600 = 3483^2 + 26060^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 691254889 - 2³ = 691254881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (691254881) 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, 151432 + ... + 155929.

It is an arithmetic number, because the mean of its divisors is an integer number (93591729).

Almost surely, 2^691254889 is an apocalyptic number.

It is an amenable number.

691254889 is a deficient number, since it is larger than the sum of its proper divisors (57478943).

691254889 is a wasteful number, since it uses less digits than its factorization.

691254889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307547.

The product of its digits is 1244160, while the sum is 52.

The square root of 691254889 is about 26291.7266264504. The cubic root of 691254889 is about 884.1909633140.

The spelling of 691254889 in words is "six hundred ninety-one million, two hundred fifty-four thousand, eight hundred eighty-nine".