7621618 has 4 divisors (see below), whose sum is σ = 11432430. Its totient is φ = 3810808.

The previous prime is 7621609. The next prime is 7621619. The reversal of 7621618 is 8161267.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8161267 = 29 ⋅281423.

It can be written as a sum of positive squares in only one way, i.e., 6315169 + 1306449 = 2513^2 + 1143^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 7621618.

It is not an unprimeable number, because it can be changed into a prime (7621619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1905403 + ... + 1905406.

Almost surely, 2^7621618 is an apocalyptic number.

7621618 is a deficient number, since it is larger than the sum of its proper divisors (3810812).

7621618 is a wasteful number, since it uses less digits than its factorization.

7621618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3810811.

The product of its digits is 4032, while the sum is 31.

The square root of 7621618 is about 2760.7278025912. The cubic root of 7621618 is about 196.7957548878.

The spelling of 7621618 in words is "seven million, six hundred twenty-one thousand, six hundred eighteen".