21515131442230 has 64 divisors (see below), whose sum is σ = 41895703249920. Its totient is φ = 7924081575424.

The previous prime is 21515131442141. The next prime is 21515131442239. The reversal of 21515131442230 is 3224413151512.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21515131442239) 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 31 ways as a sum of consecutive naturals, for example, 18112989 + ... + 19264231.

It is an arithmetic number, because the mean of its divisors is an integer number (654620363280).

Almost surely, 2^{21515131442230} is an apocalyptic number.

21515131442230 is a deficient number, since it is larger than the sum of its proper divisors (20380571807690).

21515131442230 is a wasteful number, since it uses less digits than its factorization.

21515131442230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1153653.

The product of its (nonzero) digits is 28800, while the sum is 34.

Adding to 21515131442230 its reverse (3224413151512), we get a palindrome (24739544593742).

The spelling of 21515131442230 in words is "twenty-one trillion, five hundred fifteen billion, one hundred thirty-one million, four hundred forty-two thousand, two hundred thirty".