40171855921 has 4 divisors (see below), whose sum is σ = 40175213632. Its totient is φ = 40168498212.

The previous prime is 40171855909. The next prime is 40171855961. The reversal of 40171855921 is 12955817104.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40171855921 - 2²³ = 40163467313 is a prime.

It is a super-2 number, since 2×40171855921² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40171855961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1660845 + ... + 1684858.

It is an arithmetic number, because the mean of its divisors is an integer number (10043803408).

Almost surely, 2^40171855921 is an apocalyptic number.

It is an amenable number.

40171855921 is a deficient number, since it is larger than the sum of its proper divisors (3357711).

40171855921 is a wasteful number, since it uses less digits than its factorization.

40171855921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3357710.

The product of its (nonzero) digits is 100800, while the sum is 43.

The spelling of 40171855921 in words is "forty billion, one hundred seventy-one million, eight hundred fifty-five thousand, nine hundred twenty-one".