23778905 has 4 divisors (see below), whose sum is σ = 28534692. Its totient is φ = 19023120.

The previous prime is 23778877. The next prime is 23778907. The reversal of 23778905 is 50987732.

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 10214416 + 13564489 = 3196^2 + 3683^2 .

It is not a de Polignac number, because 23778905 - 2⁸ = 23778649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23778907) 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, 2377886 + ... + 2377895.

It is an arithmetic number, because the mean of its divisors is an integer number (7133673).

Almost surely, 2^23778905 is an apocalyptic number.

It is an amenable number.

23778905 is a deficient number, since it is larger than the sum of its proper divisors (4755787).

23778905 is an equidigital number, since it uses as much as digits as its factorization.

23778905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4755786.

The product of its (nonzero) digits is 105840, while the sum is 41.

The square root of 23778905 is about 4876.3618610599. The cubic root of 23778905 is about 287.5614185103.

The spelling of 23778905 in words is "twenty-three million, seven hundred seventy-eight thousand, nine hundred five".