73818821 has 2 divisors, whose sum is σ = 73818822. Its totient is φ = 73818820.

The previous prime is 73818809. The next prime is 73818889. The reversal of 73818821 is 12881837.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72165025 + 1653796 = 8495^2 + 1286^2 .

It is a cyclic number.

It is not a de Polignac number, because 73818821 - 2⁶ = 73818757 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73818221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36909410 + 36909411.

It is an arithmetic number, because the mean of its divisors is an integer number (36909411).

Almost surely, 2^73818821 is an apocalyptic number.

It is an amenable number.

73818821 is a deficient number, since it is larger than the sum of its proper divisors (1).

73818821 is an equidigital number, since it uses as much as digits as its factorization.

73818821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21504, while the sum is 38.

The square root of 73818821 is about 8591.7879978500. The cubic root of 73818821 is about 419.4907300523.

The spelling of 73818821 in words is "seventy-three million, eight hundred eighteen thousand, eight hundred twenty-one".