1021251022400 has 252 divisors, whose sum is σ = 2930225903316. Its totient is φ = 349300224000.

The previous prime is 1021251022397. The next prime is 1021251022427. The reversal of 1021251022400 is 42201521201.

It can be written as a sum of positive squares in 6 ways, for example, as 336845587456 + 684405434944 = 580384^2 + 827288^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 32990930 + ... + 33021870.

Almost surely, 2^{1021251022400} is an apocalyptic number.

1021251022400 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 1021251022400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1465112951658).

1021251022400 is an abundant number, since it is smaller than the sum of its proper divisors (1908974880916).

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

1021251022400 is a wasteful number, since it uses less digits than its factorization.

1021251022400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31398 (or 31376 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

Adding to 1021251022400 its reverse (42201521201), we get a palindrome (1063452543601).

The spelling of 1021251022400 in words is "one trillion, twenty-one billion, two hundred fifty-one million, twenty-two thousand, four hundred".