39845551573 has 4 divisors (see below), whose sum is σ = 41219536140. Its totient is φ = 38471567008.

The previous prime is 39845551549. The next prime is 39845551591. The reversal of 39845551573 is 37515554893.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 25122884004 + 14722667569 = 158502^2 + 121337^2 .

It is a cyclic number.

It is not a de Polignac number, because 39845551573 - 2³³ = 31255616981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39845551673) 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, 686992240 + ... + 686992297.

It is an arithmetic number, because the mean of its divisors is an integer number (10304884035).

Almost surely, 2^39845551573 is an apocalyptic number.

It is an amenable number.

39845551573 is a deficient number, since it is larger than the sum of its proper divisors (1373984567).

39845551573 is a wasteful number, since it uses less digits than its factorization.

39845551573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1373984566.

The product of its digits is 11340000, while the sum is 55.

The spelling of 39845551573 in words is "thirty-nine billion, eight hundred forty-five million, five hundred fifty-one thousand, five hundred seventy-three".