21242351650 has 96 divisors (see below), whose sum is σ = 44097177600. Its totient is φ = 7560172800.

The previous prime is 21242351629. The next prime is 21242351677. The reversal of 21242351650 is 5615324212.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5418391 + ... + 5422309.

It is an arithmetic number, because the mean of its divisors is an integer number (459345600).

Almost surely, 2^21242351650 is an apocalyptic number.

21242351650 is an abundant number, since it is smaller than the sum of its proper divisors (22854825950).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21242351650 is a wasteful number, since it uses less digits than its factorization.

21242351650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4244 (or 4239 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 21242351650 its reverse (5615324212), we get a palindrome (26857675862).

The spelling of 21242351650 in words is "twenty-one billion, two hundred forty-two million, three hundred fifty-one thousand, six hundred fifty".