71887198481 has 4 divisors (see below), whose sum is σ = 82156798272. Its totient is φ = 61617598692.

The previous prime is 71887198451. The next prime is 71887198507. The reversal of 71887198481 is 18489178817.

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, and also an emirpimes, since its reverse is a distinct semiprime: 18489178817 = 251 ⋅73662067.

It is a cyclic number.

It is not a de Polignac number, because 71887198481 - 2¹⁸ = 71886936337 is a prime.

It is a super-2 number, since 2×71887198481² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71887198451) 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, 5134799885 + ... + 5134799898.

It is an arithmetic number, because the mean of its divisors is an integer number (20539199568).

Almost surely, 2^71887198481 is an apocalyptic number.

It is an amenable number.

71887198481 is a deficient number, since it is larger than the sum of its proper divisors (10269599791).

71887198481 is a wasteful number, since it uses less digits than its factorization.

71887198481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10269599790.

The product of its digits is 7225344, while the sum is 62.

The spelling of 71887198481 in words is "seventy-one billion, eight hundred eighty-seven million, one hundred ninety-eight thousand, four hundred eighty-one".