71223981 has 4 divisors (see below), whose sum is σ = 94965312. Its totient is φ = 47482652.

The previous prime is 71223967. The next prime is 71224009. The reversal of 71223981 is 18932217.

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 71223981 - 2⁶ = 71223917 is a prime.

It is a super-2 number, since 2×71223981² = 10145710938976722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71223961) 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, 11870661 + ... + 11870666.

It is an arithmetic number, because the mean of its divisors is an integer number (23741328).

Almost surely, 2^71223981 is an apocalyptic number.

It is an amenable number.

71223981 is a deficient number, since it is larger than the sum of its proper divisors (23741331).

71223981 is a wasteful number, since it uses less digits than its factorization.

71223981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23741330.

The product of its digits is 6048, while the sum is 33.

The square root of 71223981 is about 8439.4301347899. The cubic root of 71223981 is about 414.5167472085.

The spelling of 71223981 in words is "seventy-one million, two hundred twenty-three thousand, nine hundred eighty-one".