1621287396960 has 768 divisors, whose sum is σ = 6836923957248. Its totient is φ = 312599347200.

The previous prime is 1621287396929. The next prime is 1621287396961. The reversal of 1621287396960 is 696937821261.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a junction number, because it is equal to n+sod(n) for n = 1621287396894 and 1621287396903.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621287396961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 44592549 + ... + 44628891.

It is an arithmetic number, because the mean of its divisors is an integer number (8902244736).

Almost surely, 2^{1621287396960} is an apocalyptic number.

1621287396960 is a gapful number since it is divisible by the number (10) 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 1621287396960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3418461978624).

1621287396960 is an abundant number, since it is smaller than the sum of its proper divisors (5215636560288).

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

1621287396960 is a wasteful number, since it uses less digits than its factorization.

1621287396960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36467 (or 36459 counting only the distinct ones).

The product of its (nonzero) digits is 11757312, while the sum is 60.

The spelling of 1621287396960 in words is "one trillion, six hundred twenty-one billion, two hundred eighty-seven million, three hundred ninety-six thousand, nine hundred sixty".