21009169149 has 8 divisors (see below), whose sum is σ = 28471442592. Its totient is φ = 13776504240.

The previous prime is 21009169141. The next prime is 21009169199. The reversal of 21009169149 is 94196190012.

It is a happy number.

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

It is not a de Polignac number, because 21009169149 - 2³ = 21009169141 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21009169149.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21009169141) 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, 57401919 + ... + 57402284.

It is an arithmetic number, because the mean of its divisors is an integer number (3558930324).

Almost surely, 2^21009169149 is an apocalyptic number.

It is an amenable number.

21009169149 is a deficient number, since it is larger than the sum of its proper divisors (7462273443).

21009169149 is a wasteful number, since it uses less digits than its factorization.

21009169149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114804267.

The product of its (nonzero) digits is 34992, while the sum is 42.

The spelling of 21009169149 in words is "twenty-one billion, nine million, one hundred sixty-nine thousand, one hundred forty-nine".