2656042221 has 8 divisors (see below), whose sum is σ = 4047302464. Its totient is φ = 1517738400.

The previous prime is 2656042199. The next prime is 2656042237. The reversal of 2656042221 is 1222406562.

It is a happy number.

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

It is not a de Polignac number, because 2656042221 - 2¹⁰ = 2656041197 is a prime.

It is a super-2 number, since 2×2656042221² = 14109120559469225682, 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 (2656042021) 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, 63239080 + ... + 63239121.

It is an arithmetic number, because the mean of its divisors is an integer number (505912808).

Almost surely, 2^2656042221 is an apocalyptic number.

2656042221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2656042221 is a deficient number, since it is larger than the sum of its proper divisors (1391260243).

2656042221 is a wasteful number, since it uses less digits than its factorization.

2656042221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126478211.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 2656042221 is about 51536.8045284144. The cubic root of 2656042221 is about 1384.8784526697.

Adding to 2656042221 its reverse (1222406562), we get a palindrome (3878448783).

The spelling of 2656042221 in words is "two billion, six hundred fifty-six million, forty-two thousand, two hundred twenty-one".