21001554211 has 8 divisors (see below), whose sum is σ = 23252739264. Its totient is φ = 18807361320.

The previous prime is 21001554193. The next prime is 21001554227. The reversal of 21001554211 is 11245510012.

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

It is not a de Polignac number, because 21001554211 - 2⁷ = 21001554083 is a prime.

It is a super-3 number, since 3×21001554211³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21001554241) 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, 14247265 + ... + 14248738.

It is an arithmetic number, because the mean of its divisors is an integer number (2906592408).

Almost surely, 2^21001554211 is an apocalyptic number.

21001554211 is a deficient number, since it is larger than the sum of its proper divisors (2251185053).

21001554211 is a wasteful number, since it uses less digits than its factorization.

21001554211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28496081.

The product of its (nonzero) digits is 400, while the sum is 22.

The spelling of 21001554211 in words is "twenty-one billion, one million, five hundred fifty-four thousand, two hundred eleven".