71321987 has 8 divisors (see below), whose sum is σ = 82382832. Its totient is φ = 61024000.

The previous prime is 71321963. The next prime is 71322007. The reversal of 71321987 is 78912317.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71321987 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71321987.

It is not an unprimeable number, because it can be changed into a prime (71321927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 190514 + ... + 190887.

It is an arithmetic number, because the mean of its divisors is an integer number (10297854).

Almost surely, 2^71321987 is an apocalyptic number.

71321987 is a deficient number, since it is larger than the sum of its proper divisors (11060845).

71321987 is a wasteful number, since it uses less digits than its factorization.

71321987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381429.

The product of its digits is 21168, while the sum is 38.

The square root of 71321987 is about 8445.2345734148. The cubic root of 71321987 is about 414.7067885787.

It can be divided in two parts, 7132 and 1987, that added together give a palindrome (9119).

The spelling of 71321987 in words is "seventy-one million, three hundred twenty-one thousand, nine hundred eighty-seven".