71081972 has 24 divisors (see below), whose sum is σ = 135158856. Its totient is φ = 32514048.

The previous prime is 71081971. The next prime is 71081993. The reversal of 71081972 is 27918017.

It can be written as a sum of positive squares in 4 ways, for example, as 12773476 + 58308496 = 3574^2 + 7636^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71081971) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 173 + ... + 11924.

It is an arithmetic number, because the mean of its divisors is an integer number (5631619).

Almost surely, 2^71081972 is an apocalyptic number.

It is an amenable number.

71081972 is a deficient number, since it is larger than the sum of its proper divisors (64076884).

71081972 is a wasteful number, since it uses less digits than its factorization.

71081972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12227 (or 12225 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 71081972 is about 8431.0125133343. The cubic root of 71081972 is about 414.2410709835.

Adding to 71081972 its reverse (27918017), we get a palindrome (98999989).

The spelling of 71081972 in words is "seventy-one million, eighty-one thousand, nine hundred seventy-two".