2151026221 has 4 divisors (see below), whose sum is σ = 2151120672. Its totient is φ = 2150931772.

The previous prime is 2151026219. The next prime is 2151026231. The reversal of 2151026221 is 1226201512.

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.

It is a cyclic number.

It is not a de Polignac number, because 2151026221 - 2¹ = 2151026219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2151026192 and 2151026201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2151026231) 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, 10266 + ... + 66388.

It is an arithmetic number, because the mean of its divisors is an integer number (537780168).

Almost surely, 2^2151026221 is an apocalyptic number.

It is an amenable number.

2151026221 is a deficient number, since it is larger than the sum of its proper divisors (94451).

2151026221 is an equidigital number, since it uses as much as digits as its factorization.

2151026221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94450.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 2151026221 is about 46379.1571829416. The cubic root of 2151026221 is about 1290.8681976777.

Adding to 2151026221 its reverse (1226201512), we get a palindrome (3377227733).

The spelling of 2151026221 in words is "two billion, one hundred fifty-one million, twenty-six thousand, two hundred twenty-one".