78628537 has 8 divisors (see below), whose sum is σ = 84760200. Its totient is φ = 72508800.

The previous prime is 78628531. The next prime is 78628549. The reversal of 78628537 is 73582687.

It can be written as a sum of positive squares in 4 ways, for example, as 1610361 + 77018176 = 1269^2 + 8776^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78628537 - 2⁷ = 78628409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78628531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14589 + ... + 19237.

It is an arithmetic number, because the mean of its divisors is an integer number (10595025).

Almost surely, 2^78628537 is an apocalyptic number.

It is an amenable number.

78628537 is a deficient number, since it is larger than the sum of its proper divisors (6131663).

78628537 is a wasteful number, since it uses less digits than its factorization.

78628537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5963.

The product of its digits is 564480, while the sum is 46.

The square root of 78628537 is about 8867.2733689675. The cubic root of 78628537 is about 428.4104590773.

The spelling of 78628537 in words is "seventy-eight million, six hundred twenty-eight thousand, five hundred thirty-seven".