21499229916 has 36 divisors (see below), whose sum is σ = 55814070312. Its totient is φ = 6972722784.

The previous prime is 21499229897. The next prime is 21499229989. The reversal of 21499229916 is 61992299412.

It is a tau number, because it is divible by the number of its divisors (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8068950 + ... + 8071613.

It is an arithmetic number, because the mean of its divisors is an integer number (1550390842).

Almost surely, 2^21499229916 is an apocalyptic number.

It is an amenable number.

21499229916 is an abundant number, since it is smaller than the sum of its proper divisors (34314840396).

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

21499229916 is a wasteful number, since it uses less digits than its factorization.

21499229916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16140610 (or 16140605 counting only the distinct ones).

The product of its digits is 1259712, while the sum is 54.

The spelling of 21499229916 in words is "twenty-one billion, four hundred ninety-nine million, two hundred twenty-nine thousand, nine hundred sixteen".