71556220705 has 4 divisors (see below), whose sum is σ = 85867464852. Its totient is φ = 57244976560.

The previous prime is 71556220661. The next prime is 71556220727. The reversal of 71556220705 is 50702265517.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50702265517 = 229 ⋅221407273.

It can be written as a sum of positive squares in 2 ways, for example, as 40619983936 + 30936236769 = 201544^2 + 175887^2 .

It is not a de Polignac number, because 71556220705 - 2⁷ = 71556220577 is a prime.

It is a Duffinian 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, 7155622066 + ... + 7155622075.

It is an arithmetic number, because the mean of its divisors is an integer number (21466866213).

Almost surely, 2^71556220705 is an apocalyptic number.

It is an amenable number.

71556220705 is a deficient number, since it is larger than the sum of its proper divisors (14311244147).

71556220705 is a wasteful number, since it uses less digits than its factorization.

71556220705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14311244146.

The product of its (nonzero) digits is 147000, while the sum is 40.

The spelling of 71556220705 in words is "seventy-one billion, five hundred fifty-six million, two hundred twenty thousand, seven hundred five".