1221001012010 has 16 divisors (see below), whose sum is σ = 2366863500456. Its totient is φ = 450831142848.

The previous prime is 1221001012009. The next prime is 1221001012043. The reversal of 1221001012010 is 102101001221.

It can be written as a sum of positive squares in 4 ways, for example, as 518389920049 + 702611091961 = 719993^2 + 838219^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1221001011982 and 1221001012000.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4696157609 + ... + 4696157868.

Almost surely, 2^{1221001012010} is an apocalyptic number.

1221001012010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221001012010 is a deficient number, since it is larger than the sum of its proper divisors (1145862488446).

1221001012010 is a wasteful number, since it uses less digits than its factorization.

1221001012010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9392315497.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 1221001012010 its reverse (102101001221), we get a palindrome (1323102013231).

The spelling of 1221001012010 in words is "one trillion, two hundred twenty-one billion, one million, twelve thousand, ten".