21151214530 has 128 divisors (see below), whose sum is σ = 42420381696. Its totient is φ = 7560268800.

The previous prime is 21151214519. The next prime is 21151214569. The reversal of 21151214530 is 3541215112.

It is a junction number, because it is equal to n+sod(n) for n = 21151214495 and 21151214504.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 43077585 + ... + 43078075.

It is an arithmetic number, because the mean of its divisors is an integer number (331409232).

Almost surely, 2^21151214530 is an apocalyptic number.

21151214530 is an abundant number, since it is smaller than the sum of its proper divisors (21269167166).

21151214530 is a wasteful number, since it uses less digits than its factorization.

21151214530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712.

The product of its (nonzero) digits is 1200, while the sum is 25.

Adding to 21151214530 its reverse (3541215112), we get a palindrome (24692429642).

The spelling of 21151214530 in words is "twenty-one billion, one hundred fifty-one million, two hundred fourteen thousand, five hundred thirty".