84829721 has 2 divisors, whose sum is σ = 84829722. Its totient is φ = 84829720.

The previous prime is 84829691. The next prime is 84829739. The reversal of 84829721 is 12792848.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46389721 + 38440000 = 6811^2 + 6200^2 .

It is a cyclic number.

It is not a de Polignac number, because 84829721 - 2¹⁸ = 84567577 is a prime.

It is not a weakly prime, because it can be changed into another prime (84829751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42414860 + 42414861.

It is an arithmetic number, because the mean of its divisors is an integer number (42414861).

Almost surely, 2^84829721 is an apocalyptic number.

It is an amenable number.

84829721 is a deficient number, since it is larger than the sum of its proper divisors (1).

84829721 is an equidigital number, since it uses as much as digits as its factorization.

84829721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64512, while the sum is 41.

The square root of 84829721 is about 9210.3051523823. The cubic root of 84829721 is about 439.3891678977.

The spelling of 84829721 in words is "eighty-four million, eight hundred twenty-nine thousand, seven hundred twenty-one".