126888221 has 4 divisors (see below), whose sum is σ = 134352252. Its totient is φ = 119424192.

The previous prime is 126888199. The next prime is 126888241. The reversal of 126888221 is 122888621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122888621 = 97 ⋅1266893.

It can be written as a sum of positive squares in 2 ways, for example, as 113848900 + 13039321 = 10670^2 + 3611^2 .

It is a cyclic number.

It is not a de Polignac number, because 126888221 - 2¹⁴ = 126871837 is a prime.

It is a super-2 number, since 2×126888221² = 32201241257089682, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126888241) 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, 3731990 + ... + 3732023.

It is an arithmetic number, because the mean of its divisors is an integer number (33588063).

Almost surely, 2^126888221 is an apocalyptic number.

It is an amenable number.

126888221 is a deficient number, since it is larger than the sum of its proper divisors (7464031).

126888221 is an equidigital number, since it uses as much as digits as its factorization.

126888221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7464030.

The product of its digits is 24576, while the sum is 38.

The square root of 126888221 is about 11264.4671866893. The cubic root of 126888221 is about 502.5050564246.

The spelling of 126888221 in words is "one hundred twenty-six million, eight hundred eighty-eight thousand, two hundred twenty-one".