84847721 has 4 divisors (see below), whose sum is σ = 96968832. Its totient is φ = 72726612.

The previous prime is 84847657. The next prime is 84847781. The reversal of 84847721 is 12774848.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 84847721 - 2⁶ = 84847657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84847781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6060545 + ... + 6060558.

It is an arithmetic number, because the mean of its divisors is an integer number (24242208).

Almost surely, 2^84847721 is an apocalyptic number.

It is an amenable number.

84847721 is a deficient number, since it is larger than the sum of its proper divisors (12121111).

84847721 is a wasteful number, since it uses less digits than its factorization.

84847721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12121110.

The product of its digits is 100352, while the sum is 41.

The square root of 84847721 is about 9211.2822668725. The cubic root of 84847721 is about 439.4202436637.

The spelling of 84847721 in words is "eighty-four million, eight hundred forty-seven thousand, seven hundred twenty-one".