6621090 has 64 divisors (see below), whose sum is σ = 18627840. Its totient is φ = 1474560.

The previous prime is 6621071. The next prime is 6621103. The reversal of 6621090 is 901266.

It is a self number, because there is not a number n which added to its sum of digits gives 6621090.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8226 + ... + 8994.

It is an arithmetic number, because the mean of its divisors is an integer number (291060).

Almost surely, 2^6621090 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6621090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9313920).

6621090 is an abundant number, since it is smaller than the sum of its proper divisors (12006750).

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

6621090 is a wasteful number, since it uses less digits than its factorization.

6621090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 827.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 6621090 is about 2573.1478776005. The cubic root of 6621090 is about 187.7773318176. Note that the first 3 decimals are identical.

The spelling of 6621090 in words is "six million, six hundred twenty-one thousand, ninety".