1220021101 has 8 divisors (see below), whose sum is σ = 1315752984. Its totient is φ = 1124558400.

The previous prime is 1220021083. The next prime is 1220021107. The reversal of 1220021101 is 1011200221.

It can be written as a sum of positive squares in 4 ways, for example, as 241958025 + 978063076 = 15555^2 + 31274^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1220021101 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220021107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57826 + ... + 76051.

It is an arithmetic number, because the mean of its divisors is an integer number (164469123).

Almost surely, 2^1220021101 is an apocalyptic number.

It is an amenable number.

1220021101 is a deficient number, since it is larger than the sum of its proper divisors (95731883).

1220021101 is a wasteful number, since it uses less digits than its factorization.

1220021101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134591.

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

The square root of 1220021101 is about 34928.8004517762. The cubic root of 1220021101 is about 1068.5358905084.

Adding to 1220021101 its reverse (1011200221), we get a palindrome (2231221322).

The spelling of 1220021101 in words is "one billion, two hundred twenty million, twenty-one thousand, one hundred one".