216420541 has 4 divisors (see below), whose sum is σ = 216486432. Its totient is φ = 216354652.

The previous prime is 216420521. The next prime is 216420559. The reversal of 216420541 is 145024612.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216420541 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 (216420521) 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, 27745 + ... + 34678.

It is an arithmetic number, because the mean of its divisors is an integer number (54121608).

Almost surely, 2^216420541 is an apocalyptic number.

It is an amenable number.

216420541 is a deficient number, since it is larger than the sum of its proper divisors (65891).

216420541 is an equidigital number, since it uses as much as digits as its factorization.

216420541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65890.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 216420541 is about 14711.2385950334. The cubic root of 216420541 is about 600.3891373804.

The spelling of 216420541 in words is "two hundred sixteen million, four hundred twenty thousand, five hundred forty-one".