211216542 has 16 divisors (see below), whose sum is σ = 423441552. Its totient is φ = 70237440.

The previous prime is 211216531. The next prime is 211216591. The reversal of 211216542 is 245612112.

It is a super-2 number, since 2×211216542² = 89224855228875528, which contains 22 as substring.

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, 39283 + ... + 44334.

It is an arithmetic number, because the mean of its divisors is an integer number (26465097).

Almost surely, 2^211216542 is an apocalyptic number.

211216542 is an abundant number, since it is smaller than the sum of its proper divisors (212225010).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

211216542 is a wasteful number, since it uses less digits than its factorization.

211216542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84043.

The product of its digits is 960, while the sum is 24.

The square root of 211216542 is about 14533.2908179806. The cubic root of 211216542 is about 595.5377686427.

Adding to 211216542 its reverse (245612112), we get a palindrome (456828654).

The spelling of 211216542 in words is "two hundred eleven million, two hundred sixteen thousand, five hundred forty-two".