21010250555 has 16 divisors (see below), whose sum is σ = 28980621504. Its totient is φ = 14323747200.

The previous prime is 21010250531. The next prime is 21010250561. The reversal of 21010250555 is 55505201012.

It is not a de Polignac number, because 21010250555 - 2²² = 21006056251 is a prime.

It is a Duffinian 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, 1728896 + ... + 1741005.

It is an arithmetic number, because the mean of its divisors is an integer number (1811288844).

Almost surely, 2^21010250555 is an apocalyptic number.

21010250555 is a deficient number, since it is larger than the sum of its proper divisors (7970370949).

21010250555 is a wasteful number, since it uses less digits than its factorization.

21010250555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3470086.

The product of its (nonzero) digits is 2500, while the sum is 26.

Adding to 21010250555 its reverse (55505201012), we get a palindrome (76515451567).

The spelling of 21010250555 in words is "twenty-one billion, ten million, two hundred fifty thousand, five hundred fifty-five".