142210821 has 4 divisors (see below), whose sum is σ = 189614432. Its totient is φ = 94807212.

The previous prime is 142210807. The next prime is 142210829. The reversal of 142210821 is 128012241.

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 not a de Polignac number, because 142210821 - 2¹⁰ = 142209797 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 (142210829) 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, 23701801 + ... + 23701806.

It is an arithmetic number, because the mean of its divisors is an integer number (47403608).

Almost surely, 2^142210821 is an apocalyptic number.

It is an amenable number.

142210821 is a deficient number, since it is larger than the sum of its proper divisors (47403611).

142210821 is an equidigital number, since it uses as much as digits as its factorization.

142210821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47403610.

The product of its (nonzero) digits is 256, while the sum is 21.

The square root of 142210821 is about 11925.2178596452. The cubic root of 142210821 is about 521.9684035719.

The spelling of 142210821 in words is "one hundred forty-two million, two hundred ten thousand, eight hundred twenty-one".