84440421 has 16 divisors (see below), whose sum is σ = 134720320. Its totient is φ = 51963120.

The previous prime is 84440413. The next prime is 84440449. The reversal of 84440421 is 12404448.

It is a happy number.

It is not a de Polignac number, because 84440421 - 2³ = 84440413 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84440491) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119935 + ... + 120636.

It is an arithmetic number, because the mean of its divisors is an integer number (8420020).

Almost surely, 2^84440421 is an apocalyptic number.

It is an amenable number.

84440421 is a deficient number, since it is larger than the sum of its proper divisors (50279899).

84440421 is a wasteful number, since it uses less digits than its factorization.

84440421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240593 (or 240587 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 27.

The square root of 84440421 is about 9189.1469136150. The cubic root of 84440421 is about 438.7159897664.

Adding to 84440421 its reverse (12404448), we get a palindrome (96844869).

The spelling of 84440421 in words is "eighty-four million, four hundred forty thousand, four hundred twenty-one".