13219978 has 4 divisors (see below), whose sum is σ = 19829970. Its totient is φ = 6609988.

The previous prime is 13219961. The next prime is 13219979. The reversal of 13219978 is 87991231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87991231 = 109 ⋅807259.

It can be written as a sum of positive squares in only one way, i.e., 8567329 + 4652649 = 2927^2 + 2157^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 13219978.

It is not an unprimeable number, because it can be changed into a prime (13219979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3304993 + ... + 3304996.

Almost surely, 2^13219978 is an apocalyptic number.

13219978 is a deficient number, since it is larger than the sum of its proper divisors (6609992).

13219978 is an equidigital number, since it uses as much as digits as its factorization.

13219978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6609991.

The product of its digits is 27216, while the sum is 40.

The square root of 13219978 is about 3635.9287671790. The cubic root of 13219978 is about 236.4523188743.

The spelling of 13219978 in words is "thirteen million, two hundred nineteen thousand, nine hundred seventy-eight".