76771621 has 2 divisors, whose sum is σ = 76771622. Its totient is φ = 76771620.

The previous prime is 76771619. The next prime is 76771637. The reversal of 76771621 is 12617767.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41796225 + 34975396 = 6465^2 + 5914^2 .

It is a cyclic number.

It is not a de Polignac number, because 76771621 - 2¹ = 76771619 is a prime.

Together with 76771619, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (76771601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38385810 + 38385811.

It is an arithmetic number, because the mean of its divisors is an integer number (38385811).

Almost surely, 2^76771621 is an apocalyptic number.

It is an amenable number.

76771621 is a deficient number, since it is larger than the sum of its proper divisors (1).

76771621 is an equidigital number, since it uses as much as digits as its factorization.

76771621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24696, while the sum is 37.

The square root of 76771621 is about 8761.9416227227. The cubic root of 76771621 is about 425.0110649945.

The spelling of 76771621 in words is "seventy-six million, seven hundred seventy-one thousand, six hundred twenty-one".