1221021110 has 8 divisors (see below), whose sum is σ = 2197838016. Its totient is φ = 488408440.

The previous prime is 1221021103. The next prime is 1221021119. The reversal of 1221021110 is 111201221.

1221021110 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

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

It is a junction number, because it is equal to n+sod(n) for n = 1221021091 and 1221021100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221021119) 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, 61051046 + ... + 61051065.

It is an arithmetic number, because the mean of its divisors is an integer number (274729752).

Almost surely, 2^1221021110 is an apocalyptic number.

1221021110 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221021110 is a deficient number, since it is larger than the sum of its proper divisors (976816906).

1221021110 is a wasteful number, since it uses less digits than its factorization.

1221021110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122102118.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1221021110 is about 34943.1124830059. The cubic root of 1221021110 is about 1068.8277580533.

Adding to 1221021110 its reverse (111201221), we get a palindrome (1332222331).

The spelling of 1221021110 in words is "one billion, two hundred twenty-one million, twenty-one thousand, one hundred ten".