43021311997 has 2 divisors, whose sum is σ = 43021311998. Its totient is φ = 43021311996.

The previous prime is 43021311989. The next prime is 43021312003. The reversal of 43021311997 is 79911312034.

43021311997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32635867716 + 10385444281 = 180654^2 + 101909^2 .

It is a cyclic number.

It is not a de Polignac number, because 43021311997 - 2³ = 43021311989 is a prime.

It is a super-2 number, since 2×43021311997² (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 (43021311947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21510655998 + 21510655999.

It is an arithmetic number, because the mean of its divisors is an integer number (21510655999).

Almost surely, 2^43021311997 is an apocalyptic number.

It is an amenable number.

43021311997 is a deficient number, since it is larger than the sum of its proper divisors (1).

43021311997 is an equidigital number, since it uses as much as digits as its factorization.

43021311997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 40.

The spelling of 43021311997 in words is "forty-three billion, twenty-one million, three hundred eleven thousand, nine hundred ninety-seven".