212621642 has 4 divisors (see below), whose sum is σ = 318932466. Its totient is φ = 106310820.

The previous prime is 212621611. The next prime is 212621657. The reversal of 212621642 is 246126212.

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

It can be written as a sum of positive squares in only one way, i.e., 196308121 + 16313521 = 14011^2 + 4039^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53155409 + ... + 53155412.

Almost surely, 2^212621642 is an apocalyptic number.

212621642 is a deficient number, since it is larger than the sum of its proper divisors (106310824).

212621642 is a wasteful number, since it uses less digits than its factorization.

212621642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106310823.

The product of its digits is 2304, while the sum is 26.

The square root of 212621642 is about 14581.5514263744. The cubic root of 212621642 is about 596.8554390929.

Adding to 212621642 its reverse (246126212), we get a palindrome (458747854).

The spelling of 212621642 in words is "two hundred twelve million, six hundred twenty-one thousand, six hundred forty-two".