2156470217 has 4 divisors (see below), whose sum is σ = 2352512976. Its totient is φ = 1960427460.

The previous prime is 2156470193. The next prime is 2156470219. The reversal of 2156470217 is 7120746512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2156470217 - 2¹⁶ = 2156404681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2156470219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98021363 + ... + 98021384.

It is an arithmetic number, because the mean of its divisors is an integer number (588128244).

Almost surely, 2^2156470217 is an apocalyptic number.

It is an amenable number.

2156470217 is a deficient number, since it is larger than the sum of its proper divisors (196042759).

2156470217 is a wasteful number, since it uses less digits than its factorization.

2156470217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196042758.

The product of its (nonzero) digits is 23520, while the sum is 35.

The square root of 2156470217 is about 46437.8102089235. The cubic root of 2156470217 is about 1291.9562924330.

The spelling of 2156470217 in words is "two billion, one hundred fifty-six million, four hundred seventy thousand, two hundred seventeen".