21021961296336 has 1280 divisors, whose sum is σ = 80980416921600. Its totient is φ = 4513892106240.

The previous prime is 21021961296331. The next prime is 21021961296341. The reversal of 21021961296336 is 63369216912012.

It is an interprime number because it is at equal distance from previous prime (21021961296331) and next prime (21021961296341).

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021961296331) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 3738564021 + ... + 3738569643.

It is an arithmetic number, because the mean of its divisors is an integer number (63265950720).

Almost surely, 2^{21021961296336} is an apocalyptic number.

21021961296336 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21021961296336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40490208460800).

21021961296336 is an abundant number, since it is smaller than the sum of its proper divisors (59958455625264).

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

21021961296336 is a wasteful number, since it uses less digits than its factorization.

21021961296336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5904 (or 5898 counting only the distinct ones).

The product of its (nonzero) digits is 1259712, while the sum is 51.

The spelling of 21021961296336 in words is "twenty-one trillion, twenty-one billion, nine hundred sixty-one million, two hundred ninety-six thousand, three hundred thirty-six".