21011002109979 has 32 divisors (see below), whose sum is σ = 34143989967360. Its totient is φ = 11218739507712.

The previous prime is 21011002109971. The next prime is 21011002109989. The reversal of 21011002109979 is 97990120011012.

It is not a de Polignac number, because 21011002109979 - 2³ = 21011002109971 is a prime.

It is a super-2 number, since 2×21011002109979² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21011002109979.

It is not an unprimeable number, because it can be changed into a prime (21011002109971) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 211656664 + ... + 211755909.

It is an arithmetic number, because the mean of its divisors is an integer number (1066999686480).

Almost surely, 2^{21011002109979} is an apocalyptic number.

21011002109979 is a deficient number, since it is larger than the sum of its proper divisors (13132987857381).

21011002109979 is a wasteful number, since it uses less digits than its factorization.

21011002109979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423412739.

The product of its (nonzero) digits is 20412, while the sum is 42.

The spelling of 21011002109979 in words is "twenty-one trillion, eleven billion, two million, one hundred nine thousand, nine hundred seventy-nine".