709985640 has 256 divisors, whose sum is σ = 2657894400. Its totient is φ = 147723264.

The previous prime is 709985629. The next prime is 709985641. The reversal of 709985640 is 46589907.

It is a self number, because there is not a number n which added to its sum of digits gives 709985640.

It is not an unprimeable number, because it can be changed into a prime (709985641) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 862269 + ... + 863091.

It is an arithmetic number, because the mean of its divisors is an integer number (10382400).

Almost surely, 2^709985640 is an apocalyptic number.

709985640 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 709985640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1328947200).

709985640 is an abundant number, since it is smaller than the sum of its proper divisors (1947908760).

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

709985640 is a wasteful number, since it uses less digits than its factorization.

709985640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 936 (or 932 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 48.

The square root of 709985640 is about 26645.5557269876. Note that the first 3 decimals coincide. The cubic root of 709985640 is about 892.1061259777.

The spelling of 709985640 in words is "seven hundred nine million, nine hundred eighty-five thousand, six hundred forty".