21511723151011 has 8 divisors (see below), whose sum is σ = 22143559413024. Its totient is φ = 20888255581440.

The previous prime is 21511723151003. The next prime is 21511723151033. The reversal of 21511723151011 is 11015132711512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21511723151011 - 2³ = 21511723151003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21511723151411) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2092167895 + ... + 2092178176.

It is an arithmetic number, because the mean of its divisors is an integer number (2767944926628).

Almost surely, 2^{21511723151011} is an apocalyptic number.

21511723151011 is a deficient number, since it is larger than the sum of its proper divisors (631836262013).

21511723151011 is an equidigital number, since it uses as much as digits as its factorization.

21511723151011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4184346221.

The product of its (nonzero) digits is 2100, while the sum is 31.

Adding to 21511723151011 its reverse (11015132711512), we get a palindrome (32526855862523).

The spelling of 21511723151011 in words is "twenty-one trillion, five hundred eleven billion, seven hundred twenty-three million, one hundred fifty-one thousand, eleven".