85644607801 has 9 divisors (see below), whose sum is σ = 86012282959. Its totient is φ = 85278501400.

The previous prime is 85644607799. The next prime is 85644607813. The reversal of 85644607801 is 10870644658.

The square root of 85644607801 is 292651.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 53107663401 + 32536944400 = 230451^2 + 180380^2 .

It is not a de Polignac number, because 85644607801 - 2¹ = 85644607799 is a prime.

It is a super-2 number, since 2×85644607801² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85644607871) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 91013991 + ... + 91014931.

Almost surely, 2^85644607801 is an apocalyptic number.

85644607801 is the 292651-st square number.

85644607801 is the 146326-th centered octagonal number.

It is an amenable number.

85644607801 is a deficient number, since it is larger than the sum of its proper divisors (367675158).

85644607801 is an frugal number, since it uses more digits than its factorization.

85644607801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2504 (or 1252 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 49.

Multiplying 85644607801 by its sum of digits (49), we get a square (4196585782249 = 2048557²).

The spelling of 85644607801 in words is "eighty-five billion, six hundred forty-four million, six hundred seven thousand, eight hundred one".