28903440 has 40 divisors (see below), whose sum is σ = 89601408. Its totient is φ = 7707520.

The previous prime is 28903429. The next prime is 28903453. The reversal of 28903440 is 4430982.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

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

It is a junction number, because it is equal to n+sod(n) for n = 28903398 and 28903407.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59976 + ... + 60455.

Almost surely, 2^28903440 is an apocalyptic number.

28903440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28903440 is an abundant number, since it is smaller than the sum of its proper divisors (60697968).

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

28903440 is a wasteful number, since it uses less digits than its factorization.

28903440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120447 (or 120441 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 28903440 is about 5376.1919608585. The cubic root of 28903440 is about 306.8903115515.

The spelling of 28903440 in words is "twenty-eight million, nine hundred three thousand, four hundred forty".