43581999157 has 2 divisors, whose sum is σ = 43581999158. Its totient is φ = 43581999156.

The previous prime is 43581999143. The next prime is 43581999199. The reversal of 43581999157 is 75199918534.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27392236036 + 16189763121 = 165506^2 + 127239^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43581999157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 43581999095 and 43581999104.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43581999127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21790999578 + 21790999579.

It is an arithmetic number, because the mean of its divisors is an integer number (21790999579).

Almost surely, 2^43581999157 is an apocalyptic number.

It is an amenable number.

43581999157 is a deficient number, since it is larger than the sum of its proper divisors (1).

43581999157 is an equidigital number, since it uses as much as digits as its factorization.

43581999157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12247200, while the sum is 61.

The spelling of 43581999157 in words is "forty-three billion, five hundred eighty-one million, nine hundred ninety-nine thousand, one hundred fifty-seven".