2663665021 has 8 divisors (see below), whose sum is σ = 2691099864. Its totient is φ = 2636251200.

The previous prime is 2663665003. The next prime is 2663665033. The reversal of 2663665021 is 1205663662.

It can be written as a sum of positive squares in 4 ways, for example, as 1390245796 + 1273419225 = 37286^2 + 35685^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2663665021 - 2⁷ = 2663664893 is a prime.

It is a super-2 number, since 2×2663665021² = 14190222688197860882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2663665001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 437031 + ... + 443083.

It is an arithmetic number, because the mean of its divisors is an integer number (336387483).

Almost surely, 2^2663665021 is an apocalyptic number.

It is an amenable number.

2663665021 is a deficient number, since it is larger than the sum of its proper divisors (27434843).

2663665021 is a wasteful number, since it uses less digits than its factorization.

2663665021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10511.

The product of its (nonzero) digits is 77760, while the sum is 37.

The square root of 2663665021 is about 51610.7064570909. The cubic root of 2663665021 is about 1386.2020471411.

The spelling of 2663665021 in words is "two billion, six hundred sixty-three million, six hundred sixty-five thousand, twenty-one".