71927981 has 8 divisors (see below), whose sum is σ = 74022144. Its totient is φ = 69850080.

The previous prime is 71927971. The next prime is 71927983. The reversal of 71927981 is 18972917.

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

It is a cyclic number.

It is not a de Polignac number, because 71927981 - 2¹⁸ = 71665837 is a prime.

It is a super-2 number, since 2×71927981² = 10347268901472722, which 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 (71927983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5210 + ... + 13076.

It is an arithmetic number, because the mean of its divisors is an integer number (9252768).

Almost surely, 2^71927981 is an apocalyptic number.

It is an amenable number.

71927981 is a deficient number, since it is larger than the sum of its proper divisors (2094163).

71927981 is a wasteful number, since it uses less digits than its factorization.

71927981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8131.

The product of its digits is 63504, while the sum is 44.

The square root of 71927981 is about 8481.0365522146. The cubic root of 71927981 is about 415.8780094872.

The spelling of 71927981 in words is "seventy-one million, nine hundred twenty-seven thousand, nine hundred eighty-one".