71697779728 has 60 divisors (see below), whose sum is σ = 145693075840. Its totient is φ = 34174078848.

The previous prime is 71697779717. The next prime is 71697779737. The reversal of 71697779728 is 82797779617.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1029301 + ... + 1096747.

Almost surely, 2^71697779728 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 71697779728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72846537920).

71697779728 is an abundant number, since it is smaller than the sum of its proper divisors (73995296112).

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

71697779728 is a wasteful number, since it uses less digits than its factorization.

71697779728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67592 (or 67557 counting only the distinct ones).

The product of its digits is 130691232, while the sum is 70.

The spelling of 71697779728 in words is "seventy-one billion, six hundred ninety-seven million, seven hundred seventy-nine thousand, seven hundred twenty-eight".