71633989 has 4 divisors (see below), whose sum is σ = 81867424. Its totient is φ = 61400556.

The previous prime is 71633987. The next prime is 71633993. The reversal of 71633989 is 98933617.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 98933617 = 31 ⋅3191407.

It is not a de Polignac number, because 71633989 - 2¹ = 71633987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71633981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5116707 + ... + 5116720.

It is an arithmetic number, because the mean of its divisors is an integer number (20466856).

Almost surely, 2^71633989 is an apocalyptic number.

It is an amenable number.

71633989 is a deficient number, since it is larger than the sum of its proper divisors (10233435).

71633989 is a wasteful number, since it uses less digits than its factorization.

71633989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10233434.

The product of its digits is 244944, while the sum is 46.

The square root of 71633989 is about 8463.6864899404. The cubic root of 71633989 is about 415.3106282288.

The spelling of 71633989 in words is "seventy-one million, six hundred thirty-three thousand, nine hundred eighty-nine".