21001000311 has 24 divisors (see below), whose sum is σ = 31203557424. Its totient is φ = 13600880640.

The previous prime is 21001000309. The next prime is 21001000343. The reversal of 21001000311 is 11300010012.

It is not a de Polignac number, because 21001000311 - 2¹ = 21001000309 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 21001000293 and 21001000302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001007311) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 164260 + ... + 262646.

It is an arithmetic number, because the mean of its divisors is an integer number (1300148226).

Almost surely, 2^21001000311 is an apocalyptic number.

21001000311 is a deficient number, since it is larger than the sum of its proper divisors (10202557113).

21001000311 is a wasteful number, since it uses less digits than its factorization.

21001000311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99071 (or 99068 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

Adding to 21001000311 its reverse (11300010012), we get a palindrome (32301010323).

The spelling of 21001000311 in words is "twenty-one billion, one million, three hundred eleven", and thus it is an aban number.