13978115 has 8 divisors (see below), whose sum is σ = 16828560. Its totient is φ = 11145952.

The previous prime is 13978109. The next prime is 13978123. The reversal of 13978115 is 51187931.

13978115 = 31² + 32² + ... + 347².

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

It is a cyclic number.

It is not a de Polignac number, because 13978115 - 2⁴ = 13978099 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2825 + ... + 5994.

It is an arithmetic number, because the mean of its divisors is an integer number (2103570).

Almost surely, 2^13978115 is an apocalyptic number.

13978115 is a deficient number, since it is larger than the sum of its proper divisors (2850445).

13978115 is an equidigital number, since it uses as much as digits as its factorization.

13978115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9141.

The product of its digits is 7560, while the sum is 35.

The square root of 13978115 is about 3738.7317368327. The cubic root of 13978115 is about 240.8885752943. Note that the first 3 decimals are identical.

The spelling of 13978115 in words is "thirteen million, nine hundred seventy-eight thousand, one hundred fifteen".