71228297987981 has 4 divisors (see below), whose sum is σ = 71247146443200. Its totient is φ = 71209449532764.

The previous prime is 71228297987953. The next prime is 71228297987983. The reversal of 71228297987981 is 18978979282217.

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.

It is a cyclic number.

It is not a de Polignac number, because 71228297987981 - 2²² = 71228293793677 is a prime.

It is a super-3 number, since 3×71228297987981³ (a number of 43 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 71228297987896 and 71228297987905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71228297987983) 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, 9424221941 + ... + 9424229498.

It is an arithmetic number, because the mean of its divisors is an integer number (17811786610800).

Almost surely, 2^{71228297987981} is an apocalyptic number.

It is an amenable number.

71228297987981 is a deficient number, since it is larger than the sum of its proper divisors (18848455219).

71228297987981 is a wasteful number, since it uses less digits than its factorization.

71228297987981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18848455218.

The product of its digits is 1024192512, while the sum is 80.

The spelling of 71228297987981 in words is "seventy-one trillion, two hundred twenty-eight billion, two hundred ninety-seven million, nine hundred eighty-seven thousand, nine hundred eighty-one".