13641978 has 16 divisors (see below), whose sum is σ = 31181760. Its totient is φ = 3897696.

The previous prime is 13641961. The next prime is 13641989. The reversal of 13641978 is 87914631.

It is a super-2 number, since 2×13641978² = 372207127504968, which contains 22 as substring.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 162363 + ... + 162446.

It is an arithmetic number, because the mean of its divisors is an integer number (1948860).

Almost surely, 2^13641978 is an apocalyptic number.

13641978 is an abundant number, since it is smaller than the sum of its proper divisors (17539782).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13641978 is a wasteful number, since it uses less digits than its factorization.

13641978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324821.

The product of its digits is 36288, while the sum is 39.

The square root of 13641978 is about 3693.5048395799. The cubic root of 13641978 is about 238.9419745575.

The spelling of 13641978 in words is "thirteen million, six hundred forty-one thousand, nine hundred seventy-eight".