210021442 has 8 divisors (see below), whose sum is σ = 316665036. Its totient is φ = 104466432.

The previous prime is 210021439. The next prime is 210021473. The reversal of 210021442 is 244120012.

It can be written as a sum of positive squares in 2 ways, for example, as 202464441 + 7557001 = 14229^2 + 2749^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 271663 + ... + 272434.

Almost surely, 2^210021442 is an apocalyptic number.

210021442 is a deficient number, since it is larger than the sum of its proper divisors (106643594).

210021442 is a wasteful number, since it uses less digits than its factorization.

210021442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 544292.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 210021442 is about 14492.1165465918. The cubic root of 210021442 is about 594.4124246790.

Adding to 210021442 its reverse (244120012), we get a palindrome (454141454).

The spelling of 210021442 in words is "two hundred ten million, twenty-one thousand, four hundred forty-two".