83612821 has 2 divisors, whose sum is σ = 83612822. Its totient is φ = 83612820.

The previous prime is 83612791. The next prime is 83612831. The reversal of 83612821 is 12821638.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 82264900 + 1347921 = 9070^2 + 1161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-83612821 is a prime.

It is a super-2 number, since 2×83612821² = 13982207671156082, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (83612831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41806410 + 41806411.

It is an arithmetic number, because the mean of its divisors is an integer number (41806411).

Almost surely, 2^83612821 is an apocalyptic number.

It is an amenable number.

83612821 is a deficient number, since it is larger than the sum of its proper divisors (1).

83612821 is an equidigital number, since it uses as much as digits as its factorization.

83612821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 31.

The square root of 83612821 is about 9144.0046478553. The cubic root of 83612821 is about 437.2779974081.

The spelling of 83612821 in words is "eighty-three million, six hundred twelve thousand, eight hundred twenty-one".