21436328787620 has 24 divisors (see below), whose sum is σ = 46468428857088. Its totient is φ = 8297933724000.

The previous prime is 21436328787607. The next prime is 21436328787649. The reversal of 21436328787620 is 2678782363412.

It is a self number, because there is not a number n which added to its sum of digits gives 21436328787620.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17287361306 + ... + 17287362545.

It is an arithmetic number, because the mean of its divisors is an integer number (1936184535712).

Almost surely, 2^{21436328787620} is an apocalyptic number.

21436328787620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21436328787620 is an abundant number, since it is smaller than the sum of its proper divisors (25032100069468).

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

21436328787620 is a wasteful number, since it uses less digits than its factorization.

21436328787620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34574723891 (or 34574723889 counting only the distinct ones).

The product of its (nonzero) digits is 32514048, while the sum is 59.

The spelling of 21436328787620 in words is "twenty-one trillion, four hundred thirty-six billion, three hundred twenty-eight million, seven hundred eighty-seven thousand, six hundred twenty".