2157567 has 4 divisors (see below), whose sum is σ = 2876760. Its totient is φ = 1438376.

The previous prime is 2157563. The next prime is 2157587. The reversal of 2157567 is 7657512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2157567 - 2² = 2157563 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157563) 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, 359592 + ... + 359597.

It is an arithmetic number, because the mean of its divisors is an integer number (719190).

2^2157567 is an apocalyptic number.

2157567 is a deficient number, since it is larger than the sum of its proper divisors (719193).

2157567 is an equidigital number, since it uses as much as digits as its factorization.

2157567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719192.

The product of its digits is 14700, while the sum is 33.

The square root of 2157567 is about 1468.8658890450. The cubic root of 2157567 is about 129.2175285416.

Subtracting 2157567 from its reverse (7657512), we obtain a palindrome (5499945).

The spelling of 2157567 in words is "two million, one hundred fifty-seven thousand, five hundred sixty-seven".