1220100001000 has 64 divisors (see below), whose sum is σ = 2856954906000. Its totient is φ = 487711641600.

The previous prime is 1220100000971. The next prime is 1220100001009. The reversal of 1220100001000 is 1000010221.

It can be written as a sum of positive squares in 8 ways, for example, as 115696580164 + 1104403420836 = 340142^2 + 1050906^2 .

It is not an unprimeable number, because it can be changed into a prime (1220100001009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1079296 + ... + 1898704.

Almost surely, 2^{1220100001000} is an apocalyptic number.

1220100001000 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 1220100001000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1428477453000).

1220100001000 is an abundant number, since it is smaller than the sum of its proper divisors (1636854905000).

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

1220100001000 is a wasteful number, since it uses less digits than its factorization.

1220100001000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820919 (or 820905 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 1220100001000 its reverse (1000010221), we get a palindrome (1221100011221).

The spelling of 1220100001000 in words is "one trillion, two hundred twenty billion, one hundred million, one thousand".