3571921 has 4 divisors (see below), whose sum is σ = 3782052. Its totient is φ = 3361792.

The previous prime is 3571889. The next prime is 3571927. The reversal of 3571921 is 1291753.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1291753 = 19 ⋅67987.

It can be written as a sum of positive squares in 2 ways, for example, as 2873025 + 698896 = 1695^2 + 836^2 .

It is a cyclic number.

It is not a de Polignac number, because 3571921 - 2⁵ = 3571889 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3571921.

It is not an unprimeable number, because it can be changed into a prime (3571927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105040 + ... + 105073.

It is an arithmetic number, because the mean of its divisors is an integer number (945513).

Almost surely, 2^3571921 is an apocalyptic number.

It is an amenable number.

3571921 is a deficient number, since it is larger than the sum of its proper divisors (210131).

3571921 is a wasteful number, since it uses less digits than its factorization.

3571921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210130.

The product of its digits is 1890, while the sum is 28.

The square root of 3571921 is about 1889.9526449094. The cubic root of 3571921 is about 152.8623792757.

It can be divided in two parts, 357 and 1921, that added together give a triangular number (2278 = T₆₇).

The spelling of 3571921 in words is "three million, five hundred seventy-one thousand, nine hundred twenty-one".