271561921 has 4 divisors (see below), whose sum is σ = 275615152. Its totient is φ = 267508692.

The previous prime is 271561903. The next prime is 271561931. The reversal of 271561921 is 129165172.

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 271561921 - 2¹⁹ = 271037633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (271561931) 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, 2026515 + ... + 2026648.

It is an arithmetic number, because the mean of its divisors is an integer number (68903788).

Almost surely, 2^271561921 is an apocalyptic number.

It is an amenable number.

271561921 is a deficient number, since it is larger than the sum of its proper divisors (4053231).

271561921 is an equidigital number, since it uses as much as digits as its factorization.

271561921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4053230.

The product of its digits is 7560, while the sum is 34.

The square root of 271561921 is about 16479.1359300177. The cubic root of 271561921 is about 647.5743287609.

The spelling of 271561921 in words is "two hundred seventy-one million, five hundred sixty-one thousand, nine hundred twenty-one".