6420540 has 48 divisors (see below), whose sum is σ = 20547072. Its totient is φ = 1467456.

The previous prime is 6420523. The next prime is 6420587. The reversal of 6420540 is 450246.

It is a happy number.

6420540 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a zygodrome in base 2.

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, 7224 + ... + 8063.

It is an arithmetic number, because the mean of its divisors is an integer number (428064).

Almost surely, 2^6420540 is an apocalyptic number.

6420540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6420540 is an abundant number, since it is smaller than the sum of its proper divisors (14126532).

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

6420540 is a wasteful number, since it uses less digits than its factorization.

6420540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15306 (or 15304 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 6420540 is about 2533.8784501234. The cubic root of 6420540 is about 185.8619625613.

Adding to 6420540 its reverse (450246), we get a palindrome (6870786).

The spelling of 6420540 in words is "six million, four hundred twenty thousand, five hundred forty".