71376781 has 12 divisors (see below), whose sum is σ = 83405820. Its totient is φ = 60903360.

The previous prime is 71376769. The next prime is 71376803. The reversal of 71376781 is 18767317.

It can be written as a sum of positive squares in 2 ways, for example, as 44689225 + 26687556 = 6685^2 + 5166^2 .

It is not a de Polignac number, because 71376781 - 2²⁵ = 37822349 is a prime.

It is a super-2 number, since 2×71376781² = 10189289731843922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71376881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8041 + ... + 14401.

It is an arithmetic number, because the mean of its divisors is an integer number (6950485).

Almost surely, 2^71376781 is an apocalyptic number.

It is an amenable number.

71376781 is a deficient number, since it is larger than the sum of its proper divisors (12029039).

71376781 is a wasteful number, since it uses less digits than its factorization.

71376781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6604 (or 6597 counting only the distinct ones).

The product of its digits is 49392, while the sum is 40.

The square root of 71376781 is about 8448.4780286156. The cubic root of 71376781 is about 414.8129626026.

The spelling of 71376781 in words is "seventy-one million, three hundred seventy-six thousand, seven hundred eighty-one".