1020400222120 has 16 divisors (see below), whose sum is σ = 2295900499860. Its totient is φ = 408160088832.

The previous prime is 1020400222117. The next prime is 1020400222129. The reversal of 1020400222120 is 212220040201.

It can be written as a sum of positive squares in 2 ways, for example, as 1020394941316 + 5280804 = 1010146^2 + 2298^2 .

It is a super-2 number, since 2×1020400222120² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1020400222094 and 1020400222103.

It is not an unprimeable number, because it can be changed into a prime (1020400222129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12755002737 + ... + 12755002816.

Almost surely, 2^{1020400222120} is an apocalyptic number.

1020400222120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1020400222120 is an abundant number, since it is smaller than the sum of its proper divisors (1275500277740).

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

1020400222120 is a wasteful number, since it uses less digits than its factorization.

1020400222120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25510005564 (or 25510005560 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 1020400222120 its reverse (212220040201), we get a palindrome (1232620262321).

The spelling of 1020400222120 in words is "one trillion, twenty billion, four hundred million, two hundred twenty-two thousand, one hundred twenty".