1221057310 has 32 divisors (see below), whose sum is σ = 2399155200. Its totient is φ = 443753760.

The previous prime is 1221057293. The next prime is 1221057311. The reversal of 1221057310 is 137501221.

It is a happy number.

It is a super-2 number, since 2×1221057310² = 2981961908608872200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221057311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 341311 + ... + 344869.

It is an arithmetic number, because the mean of its divisors is an integer number (74973600).

Almost surely, 2^1221057310 is an apocalyptic number.

1221057310 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221057310 is a deficient number, since it is larger than the sum of its proper divisors (1178097890).

1221057310 is a wasteful number, since it uses less digits than its factorization.

1221057310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6696.

The product of its (nonzero) digits is 420, while the sum is 22.

The square root of 1221057310 is about 34943.6304639343. The cubic root of 1221057310 is about 1068.8383205740.

Adding to 1221057310 its reverse (137501221), we get a palindrome (1358558531).

The spelling of 1221057310 in words is "one billion, two hundred twenty-one million, fifty-seven thousand, three hundred ten".