28429920 has 96 divisors (see below), whose sum is σ = 99519840. Its totient is φ = 7580160.

The previous prime is 28429903. The next prime is 28429931. The reversal of 28429920 is 2992482.

It is a tau number, because it is divible by the number of its divisors (96).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1030 + ... + 7610.

It is an arithmetic number, because the mean of its divisors is an integer number (1036665).

Almost surely, 2^28429920 is an apocalyptic number.

28429920 is a gapful number since it is divisible by the number (20) 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 28429920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49759920).

28429920 is an abundant number, since it is smaller than the sum of its proper divisors (71089920).

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

28429920 is a wasteful number, since it uses less digits than its factorization.

28429920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6605 (or 6591 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 28429920 is about 5331.9714927970. The cubic root of 28429920 is about 305.2051651939.

The spelling of 28429920 in words is "twenty-eight million, four hundred twenty-nine thousand, nine hundred twenty".