71993491 has 2 divisors, whose sum is σ = 71993492. Its totient is φ = 71993490.

The previous prime is 71993479. The next prime is 71993513. The reversal of 71993491 is 19439917.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 71993491 - 2¹⁵ = 71960723 is a prime.

It is not a weakly prime, because it can be changed into another prime (71993891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35996745 + 35996746.

It is an arithmetic number, because the mean of its divisors is an integer number (35996746).

Almost surely, 2^71993491 is an apocalyptic number.

71993491 is a deficient number, since it is larger than the sum of its proper divisors (1).

71993491 is an equidigital number, since it uses as much as digits as its factorization.

71993491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 61236, while the sum is 43.

The square root of 71993491 is about 8484.8978190665. The cubic root of 71993491 is about 416.0042278755.

The spelling of 71993491 in words is "seventy-one million, nine hundred ninety-three thousand, four hundred ninety-one".