21152220142 has 16 divisors (see below), whose sum is σ = 32755588992. Its totient is φ = 10233768960.

The previous prime is 21152220121. The next prime is 21152220143. The reversal of 21152220142 is 24102225112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21152220143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 794958 + ... + 821134.

It is an arithmetic number, because the mean of its divisors is an integer number (2047224312).

Almost surely, 2^21152220142 is an apocalyptic number.

21152220142 is a deficient number, since it is larger than the sum of its proper divisors (11603368850).

21152220142 is a wasteful number, since it uses less digits than its factorization.

21152220142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39243.

The product of its (nonzero) digits is 640, while the sum is 22.

Adding to 21152220142 its reverse (24102225112), we get a palindrome (45254445254).

The spelling of 21152220142 in words is "twenty-one billion, one hundred fifty-two million, two hundred twenty thousand, one hundred forty-two".