71511641 has 2 divisors, whose sum is σ = 71511642. Its totient is φ = 71511640.

The previous prime is 71511613. The next prime is 71511679. The reversal of 71511641 is 14611517.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55190041 + 16321600 = 7429^2 + 4040^2 .

It is a cyclic number.

It is not a de Polignac number, because 71511641 - 2¹⁴ = 71495257 is a prime.

It is a super-2 number, since 2×71511641² = 10227829597025762, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 71511641.

It is not a weakly prime, because it can be changed into another prime (71511691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35755820 + 35755821.

It is an arithmetic number, because the mean of its divisors is an integer number (35755821).

Almost surely, 2^71511641 is an apocalyptic number.

It is an amenable number.

71511641 is a deficient number, since it is larger than the sum of its proper divisors (1).

71511641 is an equidigital number, since it uses as much as digits as its factorization.

71511641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 840, while the sum is 26.

The square root of 71511641 is about 8456.4555813887. The cubic root of 71511641 is about 415.0740488179.

The spelling of 71511641 in words is "seventy-one million, five hundred eleven thousand, six hundred forty-one".