7647990 has 64 divisors (see below), whose sum is σ = 21288960. Its totient is φ = 1722240.

The previous prime is 7647989. The next prime is 7648001. The reversal of 7647990 is 997467.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is a nialpdrome in base 15.

It is a congruent number.

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, 16360 + ... + 16820.

It is an arithmetic number, because the mean of its divisors is an integer number (332640).

Almost surely, 2^7647990 is an apocalyptic number.

7647990 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is a pronic number, being equal to 2765×2766.

It is a practical number, because each smaller number is the sum of distinct divisors of 7647990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10644480).

7647990 is an abundant number, since it is smaller than the sum of its proper divisors (13640970).

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

7647990 is a wasteful number, since it uses less digits than its factorization.

7647990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557.

The product of its (nonzero) digits is 95256, while the sum is 42.

The square root of 7647990 is about 2765.4999548002. The cubic root of 7647990 is about 197.0224750398.

The spelling of 7647990 in words is "seven million, six hundred forty-seven thousand, nine hundred ninety".