21510250052 has 6 divisors (see below), whose sum is σ = 37642937598. Its totient is φ = 10755125024.

The previous prime is 21510250019. The next prime is 21510250057. The reversal of 21510250052 is 25005201512.

It can be written as a sum of positive squares in only one way, i.e., 17146854916 + 4363395136 = 130946^2 + 66056^2 .

It is not an unprimeable number, because it can be changed into a prime (21510250057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2688781253 + ... + 2688781260.

It is an arithmetic number, because the mean of its divisors is an integer number (6273822933).

Almost surely, 2^21510250052 is an apocalyptic number.

It is an amenable number.

21510250052 is a deficient number, since it is larger than the sum of its proper divisors (16132687546).

21510250052 is a wasteful number, since it uses less digits than its factorization.

21510250052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5377562517 (or 5377562515 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 23.

Adding to 21510250052 its reverse (25005201512), we get a palindrome (46515451564).

The spelling of 21510250052 in words is "twenty-one billion, five hundred ten million, two hundred fifty thousand, fifty-two".