6420900 has 72 divisors (see below), whose sum is σ = 19686240. Its totient is φ = 1610240.

The previous prime is 6420899. The next prime is 6420901. The reversal of 6420900 is 90246.

It is an interprime number because it is at equal distance from previous prime (6420899) and next prime (6420901).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (6420901) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4471 + ... + 5729.

It is an arithmetic number, because the mean of its divisors is an integer number (273420).

Almost surely, 2^6420900 is an apocalyptic number.

6420900 is a gapful number since it is divisible by the number (60) 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 6420900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9843120).

6420900 is an abundant number, since it is smaller than the sum of its proper divisors (13265340).

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

6420900 is a wasteful number, since it uses less digits than its factorization.

6420900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1293 (or 1286 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 6420900 is about 2533.9494864736. The cubic root of 6420900 is about 185.8654362596.

The spelling of 6420900 in words is "six million, four hundred twenty thousand, nine hundred".