15978312 has 96 divisors (see below), whose sum is σ = 50544000. Its totient is φ = 4558176.

The previous prime is 15978311. The next prime is 15978323. The reversal of 15978312 is 21387951.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (15978311) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24373 + ... + 25019.

It is an arithmetic number, because the mean of its divisors is an integer number (526500).

Almost surely, 2^15978312 is an apocalyptic number.

15978312 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15978312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25272000).

15978312 is an abundant number, since it is smaller than the sum of its proper divisors (34565688).

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

15978312 is a wasteful number, since it uses less digits than its factorization.

15978312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680 (or 659 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 15978312 is about 3997.2880806867. The cubic root of 15978312 is about 251.8703036312.

It can be divided in two parts, 15978 and 312, that added together give a triangular number (16290 = T₁₈₀).

The spelling of 15978312 in words is "fifteen million, nine hundred seventy-eight thousand, three hundred twelve".