1221211010 has 16 divisors (see below), whose sum is σ = 2230989696. Its totient is φ = 481193328.

The previous prime is 1221210989. The next prime is 1221211021. The reversal of 1221211010 is 101121221.

It is a junction number, because it is equal to n+sod(n) for n = 1221210982 and 1221211000.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 910682 + ... + 912021.

It is an arithmetic number, because the mean of its divisors is an integer number (139436856).

Almost surely, 2^1221211010 is an apocalyptic number.

1221211010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221211010 is a deficient number, since it is larger than the sum of its proper divisors (1009778686).

1221211010 is a wasteful number, since it uses less digits than its factorization.

1221211010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1822777.

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

The square root of 1221211010 is about 34945.8296510471. The cubic root of 1221211010 is about 1068.8831651952.

Adding to 1221211010 its reverse (101121221), we get a palindrome (1322332231).

The spelling of 1221211010 in words is "one billion, two hundred twenty-one million, two hundred eleven thousand, ten".