689145845 has 4 divisors (see below), whose sum is σ = 826975020. Its totient is φ = 551316672.

The previous prime is 689145781. The next prime is 689145859. The reversal of 689145845 is 548541986.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 95687524 + 593458321 = 9782^2 + 24361^2 .

It is a cyclic number.

It is not a de Polignac number, because 689145845 - 2⁶ = 689145781 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 689145793 and 689145802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68914580 + ... + 68914589.

It is an arithmetic number, because the mean of its divisors is an integer number (206743755).

Almost surely, 2^689145845 is an apocalyptic number.

It is an amenable number.

689145845 is a deficient number, since it is larger than the sum of its proper divisors (137829175).

689145845 is a wasteful number, since it uses less digits than its factorization.

689145845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137829174.

The product of its digits is 1382400, while the sum is 50.

The square root of 689145845 is about 26251.5874758080. The cubic root of 689145845 is about 883.2908142186.

The spelling of 689145845 in words is "six hundred eighty-nine million, one hundred forty-five thousand, eight hundred forty-five".