42991097 has 2 divisors, whose sum is σ = 42991098. Its totient is φ = 42991096.

The previous prime is 42991093. The next prime is 42991121. The reversal of 42991097 is 79019924.

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., 41783296 + 1207801 = 6464^2 + 1099^2 .

It is a cyclic number.

It is not a de Polignac number, because 42991097 - 2² = 42991093 is a prime.

It is not a weakly prime, because it can be changed into another prime (42991093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21495548 + 21495549.

It is an arithmetic number, because the mean of its divisors is an integer number (21495549).

Almost surely, 2^42991097 is an apocalyptic number.

It is an amenable number.

42991097 is a deficient number, since it is larger than the sum of its proper divisors (1).

42991097 is an equidigital number, since it uses as much as digits as its factorization.

42991097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 41.

The square root of 42991097 is about 6556.7596417743. The cubic root of 42991097 is about 350.3156254915.

The spelling of 42991097 in words is "forty-two million, nine hundred ninety-one thousand, ninety-seven".