1221001020010 has 64 divisors (see below), whose sum is σ = 2347795134720. Its totient is φ = 456203404800.

The previous prime is 1221001019999. The next prime is 1221001020023. The reversal of 1221001020010 is 100201001221.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1335781 + ... + 2055799.

It is an arithmetic number, because the mean of its divisors is an integer number (36684298980).

Almost surely, 2^{1221001020010} is an apocalyptic number.

1221001020010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221001020010 is a deficient number, since it is larger than the sum of its proper divisors (1126794114710).

1221001020010 is a wasteful number, since it uses less digits than its factorization.

1221001020010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 720223.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 1221001020010 its reverse (100201001221), we get a palindrome (1321202021231).

The spelling of 1221001020010 in words is "one trillion, two hundred twenty-one billion, one million, twenty thousand, ten".