21655610434 has 8 divisors (see below), whose sum is σ = 32484582288. Its totient is φ = 10827416340.

The previous prime is 21655610407. The next prime is 21655610441. The reversal of 21655610434 is 43401655612.

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

It is a junction number, because it is equal to n+sod(n) for n = 21655610393 and 21655610402.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118972 + ... + 239719.

It is an arithmetic number, because the mean of its divisors is an integer number (4060572786).

Almost surely, 2^21655610434 is an apocalyptic number.

21655610434 is a deficient number, since it is larger than the sum of its proper divisors (10828971854).

21655610434 is a wasteful number, since it uses less digits than its factorization.

21655610434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 388880.

The product of its (nonzero) digits is 86400, while the sum is 37.

The spelling of 21655610434 in words is "twenty-one billion, six hundred fifty-five million, six hundred ten thousand, four hundred thirty-four".