2151515 has 4 divisors (see below), whose sum is σ = 2581824. Its totient is φ = 1721208.

The previous prime is 2151511. The next prime is 2151517. The reversal of 2151515 is 5151512.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2151515 - 2² = 2151511 is a prime.

It is a Duffinian number.

2151515 is a modest number, since divided by 1515 gives 215 as remainder.

It is not an unprimeable number, because it can be changed into a prime (2151511) 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, 215147 + ... + 215156.

It is an arithmetic number, because the mean of its divisors is an integer number (645456).

2^2151515 is an apocalyptic number.

2151515 is a deficient number, since it is larger than the sum of its proper divisors (430309).

2151515 is an equidigital number, since it uses as much as digits as its factorization.

2151515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430308.

The product of its digits is 250, while the sum is 20.

The square root of 2151515 is about 1466.8043495981. The cubic root of 2151515 is about 129.0965965195.

The spelling of 2151515 in words is "two million, one hundred fifty-one thousand, five hundred fifteen".