2151281 has 8 divisors (see below), whose sum is σ = 2360064. Its totient is φ = 1944720.

The previous prime is 2151271. The next prime is 2151283. The reversal of 2151281 is 1821512.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2151281 is a prime.

It is a super-2 number, since 2×2151281² = 9256019881922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2151283) 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, 2015 + ... + 2891.

It is an arithmetic number, because the mean of its divisors is an integer number (295008).

2^2151281 is an apocalyptic number.

It is an amenable number.

2151281 is a deficient number, since it is larger than the sum of its proper divisors (208783).

2151281 is a wasteful number, since it uses less digits than its factorization.

2151281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111.

The product of its digits is 160, while the sum is 20.

The square root of 2151281 is about 1466.7245821899. The cubic root of 2151281 is about 129.0919161433.

Adding to 2151281 its reverse (1821512), we get a palindrome (3972793).

The spelling of 2151281 in words is "two million, one hundred fifty-one thousand, two hundred eighty-one".