6618961 has 4 divisors (see below), whose sum is σ = 6624112. Its totient is φ = 6613812.

The previous prime is 6618959. The next prime is 6618971. The reversal of 6618961 is 1698166.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1698166 = 2 ⋅849083.

It is a cyclic number.

It is not a de Polignac number, because 6618961 - 2¹ = 6618959 is a prime.

It is an Ulam number.

It is a Duffinian number.

6618961 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6618961.

It is not an unprimeable number, because it can be changed into a prime (6618901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1126 + ... + 3808.

It is an arithmetic number, because the mean of its divisors is an integer number (1656028).

Almost surely, 2^6618961 is an apocalyptic number.

It is an amenable number.

6618961 is a deficient number, since it is larger than the sum of its proper divisors (5151).

6618961 is a wasteful number, since it uses less digits than its factorization.

6618961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5150.

The product of its digits is 15552, while the sum is 37.

The square root of 6618961 is about 2572.7341487219. The cubic root of 6618961 is about 187.7572031683.

The spelling of 6618961 in words is "six million, six hundred eighteen thousand, nine hundred sixty-one".