1021254656400 has 720 divisors, whose sum is σ = 4027050787968. Its totient is φ = 237468672000.

The previous prime is 1021254656377. The next prime is 1021254656449. The reversal of 1021254656400 is 46564521201.

1021254656400 is a `hidden beast` number, since 1 + 0 + 2 + 1 + 2 + 5 + 4 + 6 + 5 + 640 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×1021254656400² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 143 ways as a sum of consecutive naturals, for example, 104024292 + ... + 104034108.

Almost surely, 2^{1021254656400} is an apocalyptic number.

1021254656400 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 1021254656400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2013525393984).

1021254656400 is an abundant number, since it is smaller than the sum of its proper divisors (3005796131568).

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

1021254656400 is a wasteful number, since it uses less digits than its factorization.

1021254656400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9960 (or 9946 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The spelling of 1021254656400 in words is "one trillion, twenty-one billion, two hundred fifty-four million, six hundred fifty-six thousand, four hundred".