21234666516 has 48 divisors (see below), whose sum is σ = 56650191360. Its totient is φ = 6064431840.

The previous prime is 21234666511. The next prime is 21234666571. The reversal of 21234666516 is 61566643212.

It is a super-2 number, since 2×21234666516² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21234666511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145855 + ... + 252473.

It is an arithmetic number, because the mean of its divisors is an integer number (1180212320).

Almost surely, 2^21234666516 is an apocalyptic number.

It is an amenable number.

21234666516 is an abundant number, since it is smaller than the sum of its proper divisors (35415524844).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21234666516 is a wasteful number, since it uses less digits than its factorization.

21234666516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109004 (or 109002 counting only the distinct ones).

The product of its digits is 311040, while the sum is 42.

The spelling of 21234666516 in words is "twenty-one billion, two hundred thirty-four million, six hundred sixty-six thousand, five hundred sixteen".