15681420 has 36 divisors (see below), whose sum is σ = 47567520. Its totient is φ = 4181664.

The previous prime is 15681401. The next prime is 15681437. The reversal of 15681420 is 2418651.

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43380 + ... + 43739.

It is an arithmetic number, because the mean of its divisors is an integer number (1321320).

Almost surely, 2^15681420 is an apocalyptic number.

15681420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15681420 is an abundant number, since it is smaller than the sum of its proper divisors (31886100).

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

15681420 is a wasteful number, since it uses less digits than its factorization.

15681420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87134 (or 87129 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 15681420 is about 3959.9772726621. The cubic root of 15681420 is about 250.3005452122.

The spelling of 15681420 in words is "fifteen million, six hundred eighty-one thousand, four hundred twenty".