1021281323400 has 1728 divisors, whose sum is σ = 4243659638400. Its totient is φ = 226143498240.

The previous prime is 1021281323369. The next prime is 1021281323441. The reversal of 1021281323400 is 43231821201.

1021281323400 is a `hidden beast` number, since 1 + 0 + 2 + 128 + 132 + 3 + 400 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 7454608132 + ... + 7454608268.

It is an arithmetic number, because the mean of its divisors is an integer number (2455821550).

Almost surely, 2^{1021281323400} is an apocalyptic number.

1021281323400 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 1021281323400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2121829819200).

1021281323400 is an abundant number, since it is smaller than the sum of its proper divisors (3222378315000).

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

1021281323400 is a wasteful number, since it uses less digits than its factorization.

1021281323400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232 (or 202 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The spelling of 1021281323400 in words is "one trillion, twenty-one billion, two hundred eighty-one million, three hundred twenty-three thousand, four hundred".