76716821 has 4 divisors (see below), whose sum is σ = 77688000. Its totient is φ = 75745644.

The previous prime is 76716797. The next prime is 76716823. The reversal of 76716821 is 12861767.

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 76716821 - 2²⁶ = 9607957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (76716823) 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, 485471 + ... + 485628.

It is an arithmetic number, because the mean of its divisors is an integer number (19422000).

Almost surely, 2^76716821 is an apocalyptic number.

It is an amenable number.

76716821 is a deficient number, since it is larger than the sum of its proper divisors (971179).

76716821 is an equidigital number, since it uses as much as digits as its factorization.

76716821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 971178.

The product of its digits is 28224, while the sum is 38.

The square root of 76716821 is about 8758.8139037201. The cubic root of 76716821 is about 424.9099158550.

The spelling of 76716821 in words is "seventy-six million, seven hundred sixteen thousand, eight hundred twenty-one".