1221213310 has 16 divisors (see below), whose sum is σ = 2200207536. Its totient is φ = 488035648.

The previous prime is 1221213293. The next prime is 1221213311. The reversal of 1221213310 is 133121221.

It is a super-2 number, since 2×1221213310² = 2982723897042312200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221213311) 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, 44692 + ... + 66631.

It is an arithmetic number, because the mean of its divisors is an integer number (137512971).

Almost surely, 2^1221213310 is an apocalyptic number.

1221213310 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221213310 is a deficient number, since it is larger than the sum of its proper divisors (978994226).

1221213310 is a wasteful number, since it uses less digits than its factorization.

1221213310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112427.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1221213310 is about 34945.8625591071. The cubic root of 1221213310 is about 1068.8838362312.

Adding to 1221213310 its reverse (133121221), we get a palindrome (1354334531).

The spelling of 1221213310 in words is "one billion, two hundred twenty-one million, two hundred thirteen thousand, three hundred ten".