689955157872 has 400 divisors, whose sum is σ = 2116500249600. Its totient is φ = 216635005440.

The previous prime is 689955157849. The next prime is 689955157909. The reversal of 689955157872 is 278751559986.

689955157872 is a `hidden beast` number, since 68 + 9 + 9 + 551 + 5 + 7 + 8 + 7 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 689955157872.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1093430997 + ... + 1093431627.

It is an arithmetic number, because the mean of its divisors is an integer number (5291250624).

Almost surely, 2^689955157872 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 689955157872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1058250124800).

689955157872 is an abundant number, since it is smaller than the sum of its proper divisors (1426545091728).

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

689955157872 is a wasteful number, since it uses less digits than its factorization.

689955157872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1346 (or 1331 counting only the distinct ones).

The product of its digits is 381024000, while the sum is 72.

The spelling of 689955157872 in words is "six hundred eighty-nine billion, nine hundred fifty-five million, one hundred fifty-seven thousand, eight hundred seventy-two".