2125821 has 8 divisors (see below), whose sum is σ = 2957760. Its totient is φ = 1355552.

The previous prime is 2125819. The next prime is 2125831. The reversal of 2125821 is 1285212.

It is a happy number.

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 2125821 - 2¹ = 2125819 is a prime.

It is a super-2 number, since 2×2125821² = 9038229848082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2125801) 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, 15336 + ... + 15473.

It is an arithmetic number, because the mean of its divisors is an integer number (369720).

2^2125821 is an apocalyptic number.

It is an amenable number.

2125821 is a deficient number, since it is larger than the sum of its proper divisors (831939).

2125821 is a wasteful number, since it uses less digits than its factorization.

It is an anagram of its base 11 representation: 2125821 = (1222185)₁₁.

2125821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30835.

The product of its digits is 320, while the sum is 21.

The square root of 2125821 is about 1458.0195471941. The cubic root of 2125821 is about 128.5806344378.

The spelling of 2125821 in words is "two million, one hundred twenty-five thousand, eight hundred twenty-one".