2157638 has 16 divisors (see below), whose sum is σ = 3720480. Its totient is φ = 919296.

The previous prime is 2157587. The next prime is 2157641. The reversal of 2157638 is 8367512.

It is a happy number.

It is a d-powerful number, because it can be written as 2²¹ + 1 + 5³ + 7 + 6⁴ + 3¹⁰ + 8 .

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2870 + ... + 3542.

It is an arithmetic number, because the mean of its divisors is an integer number (232530).

2^2157638 is an apocalyptic number.

2157638 is a deficient number, since it is larger than the sum of its proper divisors (1562842).

2157638 is a wasteful number, since it uses less digits than its factorization.

2157638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 911.

The product of its digits is 10080, while the sum is 32.

The square root of 2157638 is about 1468.8900571520. The cubic root of 2157638 is about 129.2189459320.

The spelling of 2157638 in words is "two million, one hundred fifty-seven thousand, six hundred thirty-eight".