2151233421 has 4 divisors (see below), whose sum is σ = 2868311232. Its totient is φ = 1434155612.

The previous prime is 2151233419. The next prime is 2151233443. The reversal of 2151233421 is 1243321512.

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.

It is a cyclic number.

It is not a de Polignac number, because 2151233421 - 2¹ = 2151233419 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2151233391 and 2151233400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2151233471) 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, 358538901 + ... + 358538906.

It is an arithmetic number, because the mean of its divisors is an integer number (717077808).

Almost surely, 2^2151233421 is an apocalyptic number.

It is an amenable number.

2151233421 is a deficient number, since it is larger than the sum of its proper divisors (717077811).

2151233421 is an equidigital number, since it uses as much as digits as its factorization.

2151233421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 717077810.

The product of its digits is 1440, while the sum is 24.

The square root of 2151233421 is about 46381.3908911753. The cubic root of 2151233421 is about 1290.9096444533.

Adding to 2151233421 its reverse (1243321512), we get a palindrome (3394554933).

The spelling of 2151233421 in words is "two billion, one hundred fifty-one million, two hundred thirty-three thousand, four hundred twenty-one".