21155230430 has 32 divisors (see below), whose sum is σ = 39019252608. Its totient is φ = 8253356800.

The previous prime is 21155230409. The next prime is 21155230483. The reversal of 21155230430 is 3403255112.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21155230430.

It is a congruent number.

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, 2415860 + ... + 2424600.

It is an arithmetic number, because the mean of its divisors is an integer number (1219351644).

Almost surely, 2^21155230430 is an apocalyptic number.

21155230430 is a deficient number, since it is larger than the sum of its proper divisors (17864022178).

21155230430 is a wasteful number, since it uses less digits than its factorization.

21155230430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14692.

The product of its (nonzero) digits is 3600, while the sum is 26.

Adding to 21155230430 its reverse (3403255112), we get a palindrome (24558485542).

The spelling of 21155230430 in words is "twenty-one billion, one hundred fifty-five million, two hundred thirty thousand, four hundred thirty".