84311921 has 2 divisors, whose sum is σ = 84311922. Its totient is φ = 84311920.

The previous prime is 84311917. The next prime is 84311933. The reversal of 84311921 is 12911348.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77880625 + 6431296 = 8825^2 + 2536^2 .

It is a cyclic number.

It is not a de Polignac number, because 84311921 - 2² = 84311917 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (84311021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42155960 + 42155961.

It is an arithmetic number, because the mean of its divisors is an integer number (42155961).

Almost surely, 2^84311921 is an apocalyptic number.

It is an amenable number.

84311921 is a deficient number, since it is larger than the sum of its proper divisors (1).

84311921 is an equidigital number, since it uses as much as digits as its factorization.

84311921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 29.

The square root of 84311921 is about 9182.1523076020. The cubic root of 84311921 is about 438.4933332666.

The spelling of 84311921 in words is "eighty-four million, three hundred eleven thousand, nine hundred twenty-one".