71813869 has 2 divisors, whose sum is σ = 71813870. Its totient is φ = 71813868.

The previous prime is 71813849. The next prime is 71813879. The reversal of 71813869 is 96831817.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68260644 + 3553225 = 8262^2 + 1885^2 .

It is a cyclic number.

It is not a de Polignac number, because 71813869 - 2¹¹ = 71811821 is a prime.

It is a super-2 number, since 2×71813869² = 10314463561498322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71813849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35906934 + 35906935.

It is an arithmetic number, because the mean of its divisors is an integer number (35906935).

Almost surely, 2^71813869 is an apocalyptic number.

It is an amenable number.

71813869 is a deficient number, since it is larger than the sum of its proper divisors (1).

71813869 is an equidigital number, since it uses as much as digits as its factorization.

71813869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 43.

The square root of 71813869 is about 8474.3064022963. The cubic root of 71813869 is about 415.6579662848.

The spelling of 71813869 in words is "seventy-one million, eight hundred thirteen thousand, eight hundred sixty-nine".