2154121747 has 8 divisors (see below), whose sum is σ = 2159239680. Its totient is φ = 2149011720.

The previous prime is 2154121733. The next prime is 2154121763. The reversal of 2154121747 is 7471214512.

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-2154121747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2154121727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1380954 + ... + 1382512.

It is an arithmetic number, because the mean of its divisors is an integer number (269904960).

Almost surely, 2^2154121747 is an apocalyptic number.

2154121747 is a deficient number, since it is larger than the sum of its proper divisors (5117933).

2154121747 is a wasteful number, since it uses less digits than its factorization.

2154121747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3953.

The product of its digits is 15680, while the sum is 34.

The square root of 2154121747 is about 46412.5171370828. The cubic root of 2154121747 is about 1291.4871271805.

The spelling of 2154121747 in words is "two billion, one hundred fifty-four million, one hundred twenty-one thousand, seven hundred forty-seven".