40428 has 18 divisors (see below), whose sum is σ = 102284. Its totient is φ = 13464.

The previous prime is 40427. The next prime is 40429. The reversal of 40428 is 82404.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (40427) and next prime (40429).

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 6.

It is a self number, because there is not a number n which added to its sum of digits gives 40428.

It is not an unprimeable number, because it can be changed into a prime (40423) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 526 + ... + 597.

2⁴⁰⁴²⁸ is an apocalyptic number.

It is an amenable number.

40428 is an abundant number, since it is smaller than the sum of its proper divisors (61856).

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

40428 is a wasteful number, since it uses less digits than its factorization.

40428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1133 (or 1128 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 40428 is about 201.0671529614. The cubic root of 40428 is about 34.3210647297.

The spelling of 40428 in words is "forty thousand, four hundred twenty-eight".