2154243515 has 4 divisors (see below), whose sum is σ = 2585092224. Its totient is φ = 1723394808.

The previous prime is 2154243499. The next prime is 2154243521. The reversal of 2154243515 is 5153424512.

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 2154243515 - 2⁴ = 2154243499 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 215424347 + ... + 215424356.

It is an arithmetic number, because the mean of its divisors is an integer number (646273056).

Almost surely, 2^2154243515 is an apocalyptic number.

2154243515 is a deficient number, since it is larger than the sum of its proper divisors (430848709).

2154243515 is an equidigital number, since it uses as much as digits as its factorization.

2154243515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430848708.

The product of its digits is 24000, while the sum is 32.

The square root of 2154243515 is about 46413.8289198381. The cubic root of 2154243515 is about 1291.5114617446.

The spelling of 2154243515 in words is "two billion, one hundred fifty-four million, two hundred forty-three thousand, five hundred fifteen".