706686121639 has 4 divisors (see below), whose sum is σ = 706692979080. Its totient is φ = 706679264200.

The previous prime is 706686121613. The next prime is 706686121697. The reversal of 706686121639 is 936121686607.

706686121639 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-706686121639 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 706686121639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (706686121439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3271744 + ... + 3481045.

It is an arithmetic number, because the mean of its divisors is an integer number (176673244770).

Almost surely, 2^706686121639 is an apocalyptic number.

706686121639 is a deficient number, since it is larger than the sum of its proper divisors (6857441).

706686121639 is a wasteful number, since it uses less digits than its factorization.

706686121639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6857440.

The product of its (nonzero) digits is 3919104, while the sum is 55.

The spelling of 706686121639 in words is "seven hundred six billion, six hundred eighty-six million, one hundred twenty-one thousand, six hundred thirty-nine".