21435256446 has 32 divisors (see below), whose sum is σ = 46957566240. Its totient is φ = 6492896256.

The previous prime is 21435256439. The next prime is 21435256457. The reversal of 21435256446 is 64465253412.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21435256398 and 21435256407.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3620311 + ... + 3626226.

It is an arithmetic number, because the mean of its divisors is an integer number (1467423945).

Almost surely, 2^21435256446 is an apocalyptic number.

21435256446 is an abundant number, since it is smaller than the sum of its proper divisors (25522309794).

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

21435256446 is a wasteful number, since it uses less digits than its factorization.

21435256446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7246588.

The product of its digits is 691200, while the sum is 42.

The spelling of 21435256446 in words is "twenty-one billion, four hundred thirty-five million, two hundred fifty-six thousand, four hundred forty-six".