76749821 has 8 divisors (see below), whose sum is σ = 77445720. Its totient is φ = 76057408.

The previous prime is 76749817. The next prime is 76749833. The reversal of 76749821 is 12894767.

It can be written as a sum of positive squares in 4 ways, for example, as 37687321 + 39062500 = 6139^2 + 6250^2 .

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 76749821 - 2² = 76749817 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 (76740821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61835 + ... + 63063.

It is an arithmetic number, because the mean of its divisors is an integer number (9680715).

Almost surely, 2^76749821 is an apocalyptic number.

It is an amenable number.

76749821 is a deficient number, since it is larger than the sum of its proper divisors (695899).

76749821 is a wasteful number, since it uses less digits than its factorization.

76749821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1743.

The product of its digits is 169344, while the sum is 44.

The square root of 76749821 is about 8760.6975178921. The cubic root of 76749821 is about 424.9708326004.

The spelling of 76749821 in words is "seventy-six million, seven hundred forty-nine thousand, eight hundred twenty-one".