21434776691 has 8 divisors (see below), whose sum is σ = 21501676800. Its totient is φ = 21367912192.

The previous prime is 21434776687. The next prime is 21434776709. The reversal of 21434776691 is 19667743412.

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

It is a cyclic number.

It is not a de Polignac number, because 21434776691 - 2² = 21434776687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21434776651) 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, 1687721 + ... + 1700373.

It is an arithmetic number, because the mean of its divisors is an integer number (2687709600).

Almost surely, 2^21434776691 is an apocalyptic number.

21434776691 is a deficient number, since it is larger than the sum of its proper divisors (66900109).

21434776691 is a wasteful number, since it uses less digits than its factorization.

21434776691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17805.

The product of its digits is 1524096, while the sum is 50.

The spelling of 21434776691 in words is "twenty-one billion, four hundred thirty-four million, seven hundred seventy-six thousand, six hundred ninety-one".