84780457 has 4 divisors (see below), whose sum is σ = 84800196. Its totient is φ = 84760720.

The previous prime is 84780407. The next prime is 84780469. The reversal of 84780457 is 75408748.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 65674816 + 19105641 = 8104^2 + 4371^2 .

It is a cyclic number.

It is not a de Polignac number, because 84780457 - 2¹⁹ = 84256169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84780407) 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, 394 + ... + 13027.

It is an arithmetic number, because the mean of its divisors is an integer number (21200049).

Almost surely, 2^84780457 is an apocalyptic number.

It is an amenable number.

84780457 is a deficient number, since it is larger than the sum of its proper divisors (19739).

84780457 is a wasteful number, since it uses less digits than its factorization.

84780457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19738.

The product of its (nonzero) digits is 250880, while the sum is 43.

The square root of 84780457 is about 9207.6303683412. The cubic root of 84780457 is about 439.3040944930.

The spelling of 84780457 in words is "eighty-four million, seven hundred eighty thousand, four hundred fifty-seven".