21165061229 has 16 divisors (see below), whose sum is σ = 24046344000. Its totient is φ = 18467398656.

The previous prime is 21165061189. The next prime is 21165061231. The reversal of 21165061229 is 92216056112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21165061229 - 2¹⁶ = 21164995693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21165061289) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15482 + ... + 206324.

It is an arithmetic number, because the mean of its divisors is an integer number (1502896500).

Almost surely, 2^21165061229 is an apocalyptic number.

It is an amenable number.

21165061229 is a deficient number, since it is larger than the sum of its proper divisors (2881282771).

21165061229 is a wasteful number, since it uses less digits than its factorization.

21165061229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191324.

The product of its (nonzero) digits is 12960, while the sum is 35.

The spelling of 21165061229 in words is "twenty-one billion, one hundred sixty-five million, sixty-one thousand, two hundred twenty-nine".