40231664821 has 4 divisors (see below), whose sum is σ = 40232228652. Its totient is φ = 40231100992.

The previous prime is 40231664813. The next prime is 40231664827. The reversal of 40231664821 is 12846613204.

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 18810122500 + 21421542321 = 137150^2 + 146361^2 .

It is a cyclic number.

It is not a de Polignac number, because 40231664821 - 2³ = 40231664813 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 (40231664827) 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, 156196 + ... + 323821.

It is an arithmetic number, because the mean of its divisors is an integer number (10058057163).

Almost surely, 2^40231664821 is an apocalyptic number.

It is an amenable number.

40231664821 is a deficient number, since it is larger than the sum of its proper divisors (563831).

40231664821 is an equidigital number, since it uses as much as digits as its factorization.

40231664821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 563830.

The product of its (nonzero) digits is 55296, while the sum is 37.

The spelling of 40231664821 in words is "forty billion, two hundred thirty-one million, six hundred sixty-four thousand, eight hundred twenty-one".