1220101011 has 24 divisors (see below), whose sum is σ = 1820548080. Its totient is φ = 786805056.

The previous prime is 1220100997. The next prime is 1220101037. The reversal of 1220101011 is 1101010221.

It is a happy number.

It is not a de Polignac number, because 1220101011 - 2¹⁰ = 1220099987 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 1220100984 and 1220101002.

It is not an unprimeable number, because it can be changed into a prime (1220102011) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 47020 + ... + 68198.

It is an arithmetic number, because the mean of its divisors is an integer number (75856170).

Almost surely, 2^1220101011 is an apocalyptic number.

1220101011 is a deficient number, since it is larger than the sum of its proper divisors (600447069).

1220101011 is a wasteful number, since it uses less digits than its factorization.

1220101011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21395 (or 21392 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 1220101011 is about 34929.9443314758. The cubic root of 1220101011 is about 1068.5592192958.

Adding to 1220101011 its reverse (1101010221), we get a palindrome (2321111232).

The spelling of 1220101011 in words is "one billion, two hundred twenty million, one hundred one thousand, eleven".