1100020421 has 4 divisors (see below), whose sum is σ = 1104953472. Its totient is φ = 1095087372.

The previous prime is 1100020417. The next prime is 1100020423. The reversal of 1100020421 is 1240200011.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1240200011 = 7229 ⋅171559.

It is a cyclic number.

It is not a de Polignac number, because 1100020421 - 2² = 1100020417 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1100020423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2466191 + ... + 2466636.

It is an arithmetic number, because the mean of its divisors is an integer number (276238368).

Almost surely, 2^1100020421 is an apocalyptic number.

It is an amenable number.

1100020421 is a deficient number, since it is larger than the sum of its proper divisors (4933051).

1100020421 is an equidigital number, since it uses as much as digits as its factorization.

1100020421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4933050.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1100020421 is about 33166.5557602836. Note that the first 3 decimals coincide. The cubic root of 1100020421 is about 1032.2865033539.

Adding to 1100020421 its reverse (1240200011), we get a palindrome (2340220432).

The spelling of 1100020421 in words is "one billion, one hundred million, twenty thousand, four hundred twenty-one".