21520525421210 has 32 divisors (see below), whose sum is σ = 40073235442560. Its totient is φ = 8311264800832.

The previous prime is 21520525421209. The next prime is 21520525421287. The reversal of 21520525421210 is 1212452502512.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23329577 + ... + 24234483.

It is an arithmetic number, because the mean of its divisors is an integer number (1252288607580).

Almost surely, 2^{21520525421210} is an apocalyptic number.

21520525421210 is a deficient number, since it is larger than the sum of its proper divisors (18552710021350).

21520525421210 is a wasteful number, since it uses less digits than its factorization.

21520525421210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 986950.

The product of its (nonzero) digits is 16000, while the sum is 32.

Adding to 21520525421210 its reverse (1212452502512), we get a palindrome (22732977923722).

The spelling of 21520525421210 in words is "twenty-one trillion, five hundred twenty billion, five hundred twenty-five million, four hundred twenty-one thousand, two hundred ten".