21355415634 has 16 divisors (see below), whose sum is σ = 48812378688. Its totient is φ = 6101547312.

The previous prime is 21355415591. The next prime is 21355415651. The reversal of 21355415634 is 43651455312.

It is a happy number.

21355415634 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 21355415592 and 21355415601.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 254231097 + ... + 254231180.

It is an arithmetic number, because the mean of its divisors is an integer number (3050773668).

Almost surely, 2^21355415634 is an apocalyptic number.

21355415634 is an abundant number, since it is smaller than the sum of its proper divisors (27456963054).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21355415634 is a wasteful number, since it uses less digits than its factorization.

21355415634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 508462289.

The product of its digits is 216000, while the sum is 39.

The spelling of 21355415634 in words is "twenty-one billion, three hundred fifty-five million, four hundred fifteen thousand, six hundred thirty-four".