21541031051 has 4 divisors (see below), whose sum is σ = 21562768704. Its totient is φ = 21519293400.

The previous prime is 21541031047. The next prime is 21541031053. The reversal of 21541031051 is 15013014512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21541031051 - 2² = 21541031047 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21541031053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10867340 + ... + 10869321.

It is an arithmetic number, because the mean of its divisors is an integer number (5390692176).

Almost surely, 2^21541031051 is an apocalyptic number.

21541031051 is a deficient number, since it is larger than the sum of its proper divisors (21737653).

21541031051 is an equidigital number, since it uses as much as digits as its factorization.

21541031051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21737652.

The product of its (nonzero) digits is 600, while the sum is 23.

Adding to 21541031051 its reverse (15013014512), we get a palindrome (36554045563).

The spelling of 21541031051 in words is "twenty-one billion, five hundred forty-one million, thirty-one thousand, fifty-one".