1211000220001 has 12 divisors (see below), whose sum is σ = 1433491679956. Its totient is φ = 1016223959520.

The previous prime is 1211000219987. The next prime is 1211000220077. The reversal of 1211000220001 is 1000220001121.

It can be written as a sum of positive squares in 2 ways, for example, as 243491915601 + 967508304400 = 493449^2 + 983620^2 .

It is not a de Polignac number, because 1211000220001 - 2²³ = 1210991831393 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211000220001.

It is not an unprimeable number, because it can be changed into a prime (1211000220401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 384931746 + ... + 384934891.

Almost surely, 2^{1211000220001} is an apocalyptic number.

1211000220001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211000220001 is a deficient number, since it is larger than the sum of its proper divisors (222491459955).

1211000220001 is a wasteful number, since it uses less digits than its factorization.

1211000220001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 769866672 (or 769866661 counting only the distinct ones).

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

Adding to 1211000220001 its reverse (1000220001121), we get a palindrome (2211220221122).

It can be divided in two parts, 121 and 1000220001, that multiplied together give a palindrome (121026620121).

The spelling of 1211000220001 in words is "one trillion, two hundred eleven billion, two hundred twenty thousand, one".