71764981 has 2 divisors, whose sum is σ = 71764982. Its totient is φ = 71764980.

The previous prime is 71764967. The next prime is 71765011. The reversal of 71764981 is 18946717.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61873956 + 9891025 = 7866^2 + 3145^2 .

It is a cyclic number.

It is not a de Polignac number, because 71764981 - 2⁵ = 71764949 is a prime.

It is a super-2 number, since 2×71764981² = 10300424995860722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71764921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35882490 + 35882491.

It is an arithmetic number, because the mean of its divisors is an integer number (35882491).

Almost surely, 2^71764981 is an apocalyptic number.

It is an amenable number.

71764981 is a deficient number, since it is larger than the sum of its proper divisors (1).

71764981 is an equidigital number, since it uses as much as digits as its factorization.

71764981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84672, while the sum is 43.

The square root of 71764981 is about 8471.4214273639. The cubic root of 71764981 is about 415.5636237859.

The spelling of 71764981 in words is "seventy-one million, seven hundred sixty-four thousand, nine hundred eighty-one".