21126798051 has 8 divisors (see below), whose sum is σ = 29393806080. Its totient is φ = 13472161032.

The previous prime is 21126798047. The next prime is 21126798071. The reversal of 21126798051 is 15089762112.

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

It is not a de Polignac number, because 21126798051 - 2² = 21126798047 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21126797994 and 21126798012.

It is not an unprimeable number, because it can be changed into a prime (21126798001) 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, 153092671 + ... + 153092808.

It is an arithmetic number, because the mean of its divisors is an integer number (3674225760).

Almost surely, 2^21126798051 is an apocalyptic number.

21126798051 is a deficient number, since it is larger than the sum of its proper divisors (8267008029).

21126798051 is a wasteful number, since it uses less digits than its factorization.

21126798051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306185505.

The product of its (nonzero) digits is 60480, while the sum is 42.

The spelling of 21126798051 in words is "twenty-one billion, one hundred twenty-six million, seven hundred ninety-eight thousand, fifty-one".