78451673 has 4 divisors (see below), whose sum is σ = 79737828. Its totient is φ = 77165520.

The previous prime is 78451621. The next prime is 78451687. The reversal of 78451673 is 37615487.

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 35378704 + 43072969 = 5948^2 + 6563^2 .

It is a cyclic number.

It is not a de Polignac number, because 78451673 - 2⁶ = 78451609 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78451673.

It is not an unprimeable number, because it can be changed into a prime (78451603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 642986 + ... + 643107.

It is an arithmetic number, because the mean of its divisors is an integer number (19934457).

Almost surely, 2^78451673 is an apocalyptic number.

It is an amenable number.

78451673 is a deficient number, since it is larger than the sum of its proper divisors (1286155).

78451673 is a wasteful number, since it uses less digits than its factorization.

78451673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1286154.

The product of its digits is 141120, while the sum is 41.

The square root of 78451673 is about 8857.2949030728. The cubic root of 78451673 is about 428.0890012746.

The spelling of 78451673 in words is "seventy-eight million, four hundred fifty-one thousand, six hundred seventy-three".