71016207781 has 4 divisors (see below), whose sum is σ = 71915147200. Its totient is φ = 70117268364.

The previous prime is 71016207737. The next prime is 71016207799. The reversal of 71016207781 is 18770261017.

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 71016207781 - 2⁷ = 71016207653 is a prime.

It is a super-2 number, since 2×71016207781² (a number of 23 digits) 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 (71016204781) 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, 449469591 + ... + 449469748.

It is an arithmetic number, because the mean of its divisors is an integer number (17978786800).

Almost surely, 2^71016207781 is an apocalyptic number.

It is an amenable number.

71016207781 is a deficient number, since it is larger than the sum of its proper divisors (898939419).

71016207781 is an equidigital number, since it uses as much as digits as its factorization.

71016207781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 898939418.

The product of its (nonzero) digits is 32928, while the sum is 40.

Adding to 71016207781 its reverse (18770261017), we get a palindrome (89786468798).

The spelling of 71016207781 in words is "seventy-one billion, sixteen million, two hundred seven thousand, seven hundred eighty-one".