2154021505 has 8 divisors (see below), whose sum is σ = 2617545600. Its totient is φ = 1701404016.

The previous prime is 2154021503. The next prime is 2154021511. The reversal of 2154021505 is 5051204512.

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

It is a cyclic number.

It is not a de Polignac number, because 2154021505 - 2¹ = 2154021503 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2154021505.

It is not an unprimeable number, because it can be changed into a prime (2154021503) 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, 2726215 + ... + 2727004.

It is an arithmetic number, because the mean of its divisors is an integer number (327193200).

Almost surely, 2^2154021505 is an apocalyptic number.

It is an amenable number.

2154021505 is a deficient number, since it is larger than the sum of its proper divisors (463524095).

2154021505 is an equidigital number, since it uses as much as digits as its factorization.

2154021505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5453303.

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 2154021505 is about 46411.4372218745. The cubic root of 2154021505 is about 1291.4670937630.

The spelling of 2154021505 in words is "two billion, one hundred fifty-four million, twenty-one thousand, five hundred five".