13128778 has 8 divisors (see below), whose sum is σ = 21208068. Its totient is φ = 6059424.

The previous prime is 13128769. The next prime is 13128781. The reversal of 13128778 is 87782131.

It can be written as a sum of positive squares in 2 ways, for example, as 10673289 + 2455489 = 3267^2 + 1567^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 252451 + ... + 252502.

Almost surely, 2^13128778 is an apocalyptic number.

13128778 is a deficient number, since it is larger than the sum of its proper divisors (8079290).

13128778 is a wasteful number, since it uses less digits than its factorization.

13128778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504968.

The product of its digits is 18816, while the sum is 37.

The square root of 13128778 is about 3623.3655625675. The cubic root of 13128778 is about 235.9073297942.

The spelling of 13128778 in words is "thirteen million, one hundred twenty-eight thousand, seven hundred seventy-eight".