21250030550 has 48 divisors (see below), whose sum is σ = 46392372960. Its totient is φ = 7088808960.

The previous prime is 21250030469. The next prime is 21250030553. The reversal of 21250030550 is 5503005212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21250030553) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 807515 + ... + 833414.

It is an arithmetic number, because the mean of its divisors is an integer number (966507770).

Almost surely, 2^21250030550 is an apocalyptic number.

21250030550 is an abundant number, since it is smaller than the sum of its proper divisors (25142342410).

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

21250030550 is a wasteful number, since it uses less digits than its factorization.

21250030550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1640985 (or 1640980 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 23.

Adding to 21250030550 its reverse (5503005212), we get a palindrome (26753035762).

The spelling of 21250030550 in words is "twenty-one billion, two hundred fifty million, thirty thousand, five hundred fifty".