43420173557 has 2 divisors, whose sum is σ = 43420173558. Its totient is φ = 43420173556.

The previous prime is 43420173553. The next prime is 43420173619. The reversal of 43420173557 is 75537102434.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22441837636 + 20978335921 = 149806^2 + 144839^2 .

It is a cyclic number.

It is not a de Polignac number, because 43420173557 - 2² = 43420173553 is a prime.

It is a super-2 number, since 2×43420173557² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43420173553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21710086778 + 21710086779.

It is an arithmetic number, because the mean of its divisors is an integer number (21710086779).

Almost surely, 2^43420173557 is an apocalyptic number.

It is an amenable number.

43420173557 is a deficient number, since it is larger than the sum of its proper divisors (1).

43420173557 is an equidigital number, since it uses as much as digits as its factorization.

43420173557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 352800, while the sum is 41.

The spelling of 43420173557 in words is "forty-three billion, four hundred twenty million, one hundred seventy-three thousand, five hundred fifty-seven".