15680820 has 24 divisors (see below), whose sum is σ = 43906464. Its totient is φ = 4181536.

The previous prime is 15680807. The next prime is 15680827. The reversal of 15680820 is 2808651.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15680827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 130614 + ... + 130733.

It is an arithmetic number, because the mean of its divisors is an integer number (1829436).

Almost surely, 2^15680820 is an apocalyptic number.

15680820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15680820 is an abundant number, since it is smaller than the sum of its proper divisors (28225644).

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

15680820 is a wasteful number, since it uses less digits than its factorization.

15680820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261359 (or 261357 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 15680820 is about 3959.9015139268. The cubic root of 15680820 is about 250.2973528516.

The spelling of 15680820 in words is "fifteen million, six hundred eighty thousand, eight hundred twenty".