215642023 has 4 divisors (see below), whose sum is σ = 215679888. Its totient is φ = 215604160.

The previous prime is 215641939. The next prime is 215642027. The reversal of 215642023 is 320246512.

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 215642023 - 2⁹ = 215641511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215642027) 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, 8458 + ... + 22423.

It is an arithmetic number, because the mean of its divisors is an integer number (53919972).

Almost surely, 2^215642023 is an apocalyptic number.

215642023 is a deficient number, since it is larger than the sum of its proper divisors (37865).

215642023 is an equidigital number, since it uses as much as digits as its factorization.

215642023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37864.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 215642023 is about 14684.7547817456. The cubic root of 215642023 is about 599.6683565363.

Adding to 215642023 its reverse (320246512), we get a palindrome (535888535).

It can be divided in two parts, 2 and 15642023, that added together give a square (15642025 = 3955²).

The spelling of 215642023 in words is "two hundred fifteen million, six hundred forty-two thousand, twenty-three".