21245630246646 has 256 divisors, whose sum is σ = 48690843586560. Its totient is φ = 6130709544960.

The previous prime is 21245630246629. The next prime is 21245630246693. The reversal of 21245630246646 is 64664203654212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 31382023660 + ... + 31382024336.

It is an arithmetic number, because the mean of its divisors is an integer number (190198607760).

Almost surely, 2^{21245630246646} is an apocalyptic number.

21245630246646 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21245630246646, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24345421793280).

21245630246646 is an abundant number, since it is smaller than the sum of its proper divisors (27445213339914).

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

21245630246646 is a wasteful number, since it uses less digits than its factorization.

21245630246646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1791.

The product of its (nonzero) digits is 9953280, while the sum is 51.

The spelling of 21245630246646 in words is "twenty-one trillion, two hundred forty-five billion, six hundred thirty million, two hundred forty-six thousand, six hundred forty-six".