2171557 has 2 divisors, whose sum is σ = 2171558. Its totient is φ = 2171556.

The previous prime is 2171551. The next prime is 2171579. The reversal of 2171557 is 7551712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1153476 + 1018081 = 1074^2 + 1009^2 .

It is a cyclic number.

It is not a de Polignac number, because 2171557 - 2¹¹ = 2169509 is a prime.

It is a nialpdrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2171551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1085778 + 1085779.

It is an arithmetic number, because the mean of its divisors is an integer number (1085779).

2^2171557 is an apocalyptic number.

It is an amenable number.

2171557 is a deficient number, since it is larger than the sum of its proper divisors (1).

2171557 is an equidigital number, since it uses as much as digits as its factorization.

2171557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2450, while the sum is 28.

The square root of 2171557 is about 1473.6203717376. The cubic root of 2171557 is about 129.4962159069.

The spelling of 2171557 in words is "two million, one hundred seventy-one thousand, five hundred fifty-seven".