15978955 has 4 divisors (see below), whose sum is σ = 19174752. Its totient is φ = 12783160.

The previous prime is 15978923. The next prime is 15978967. The reversal of 15978955 is 55987951.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 15978955 - 2⁵ = 15978923 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15978899 and 15978908.

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, 1597891 + ... + 1597900.

It is an arithmetic number, because the mean of its divisors is an integer number (4793688).

Almost surely, 2^15978955 is an apocalyptic number.

15978955 is a deficient number, since it is larger than the sum of its proper divisors (3195797).

15978955 is an equidigital number, since it uses as much as digits as its factorization.

15978955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3195796.

The product of its digits is 567000, while the sum is 49.

The square root of 15978955 is about 3997.3685094072. The cubic root of 15978955 is about 251.8736821782.

The spelling of 15978955 in words is "fifteen million, nine hundred seventy-eight thousand, nine hundred fifty-five".