21798705137 has 8 divisors (see below), whose sum is σ = 23836896192. Its totient is φ = 19769929200.

The previous prime is 21798705113. The next prime is 21798705167. The reversal of 21798705137 is 73150789712.

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 21798705137 - 2³² = 17503737841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21798705167) 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, 2348933 + ... + 2358194.

It is an arithmetic number, because the mean of its divisors is an integer number (2979612024).

Almost surely, 2^21798705137 is an apocalyptic number.

It is an amenable number.

21798705137 is a deficient number, since it is larger than the sum of its proper divisors (2038191055).

21798705137 is a wasteful number, since it uses less digits than its factorization.

21798705137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4707559.

The product of its (nonzero) digits is 740880, while the sum is 50.

The spelling of 21798705137 in words is "twenty-one billion, seven hundred ninety-eight million, seven hundred five thousand, one hundred thirty-seven".