21011210355 has 32 divisors (see below), whose sum is σ = 36289244160. Its totient is φ = 10349144960.

The previous prime is 21011210351. The next prime is 21011210369. The reversal of 21011210355 is 55301211012.

It is not a de Polignac number, because 21011210355 - 2² = 21011210351 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21011210351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1040031 + ... + 1060040.

It is an arithmetic number, because the mean of its divisors is an integer number (1134038880).

Almost surely, 2^21011210355 is an apocalyptic number.

21011210355 is a deficient number, since it is larger than the sum of its proper divisors (15278033805).

21011210355 is a wasteful number, since it uses less digits than its factorization.

21011210355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100131.

The product of its (nonzero) digits is 300, while the sum is 21.

Adding to 21011210355 its reverse (55301211012), we get a palindrome (76312421367).

The spelling of 21011210355 in words is "twenty-one billion, eleven million, two hundred ten thousand, three hundred fifty-five".