15820428 has 72 divisors (see below), whose sum is σ = 41504400. Its totient is φ = 4682496.

The previous prime is 15820417. The next prime is 15820439. The reversal of 15820428 is 82402851.

15820428 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (15820417) and next prime (15820439).

It is a junction number, because it is equal to n+sod(n) for n = 15820395 and 15820404.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 58678 + ... + 58946.

It is an arithmetic number, because the mean of its divisors is an integer number (576450).

Almost surely, 2^15820428 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15820428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20752200).

15820428 is an abundant number, since it is smaller than the sum of its proper divisors (25683972).

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

15820428 is a wasteful number, since it uses less digits than its factorization.

15820428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331 (or 316 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 30.

The square root of 15820428 is about 3977.4901634071. The cubic root of 15820428 is about 251.0379671989.

The spelling of 15820428 in words is "fifteen million, eight hundred twenty thousand, four hundred twenty-eight".