428534640 has 240 divisors, whose sum is σ = 1540401408. Its totient is φ = 106389504.

The previous prime is 428534621. The next prime is 428534647. The reversal of 428534640 is 46435824.

428534640 is a `hidden beast` number, since 4 + 2 + 8 + 5 + 3 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

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

It is a junction number, because it is equal to n+sod(n) for n = 428534595 and 428534604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (428534647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1921569 + ... + 1921791.

Almost surely, 2^428534640 is an apocalyptic number.

428534640 is a gapful number since it is divisible by the number (40) 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 428534640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (770200704).

428534640 is an abundant number, since it is smaller than the sum of its proper divisors (1111866768).

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

428534640 is a wasteful number, since it uses less digits than its factorization.

428534640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 36.

The square root of 428534640 is about 20701.0782327878. The cubic root of 428534640 is about 753.9258675624.

The spelling of 428534640 in words is "four hundred twenty-eight million, five hundred thirty-four thousand, six hundred forty".