2155501 has 4 divisors (see below), whose sum is σ = 2158492. Its totient is φ = 2152512.

The previous prime is 2155499. The next prime is 2155511. The reversal of 2155501 is 1055512.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 491401 + 1664100 = 701^2 + 1290^2 .

It is a cyclic number.

It is not a de Polignac number, because 2155501 - 2¹ = 2155499 is a prime.

It is a super-2 number, since 2×2155501² = 9292369122002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2155511) 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, 325 + ... + 2101.

It is an arithmetic number, because the mean of its divisors is an integer number (539623).

2^2155501 is an apocalyptic number.

It is an amenable number.

2155501 is a deficient number, since it is larger than the sum of its proper divisors (2991).

2155501 is a wasteful number, since it uses less digits than its factorization.

2155501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2990.

The product of its (nonzero) digits is 250, while the sum is 19.

The square root of 2155501 is about 1468.1624569509. The cubic root of 2155501 is about 129.1762708548.

The spelling of 2155501 in words is "two million, one hundred fifty-five thousand, five hundred one".