1221400412 has 12 divisors (see below), whose sum is σ = 2137722720. Its totient is φ = 610622496.

The previous prime is 1221400409. The next prime is 1221400417. The reversal of 1221400412 is 2140041221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221400417) 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, 29789 + ... + 57707.

It is an arithmetic number, because the mean of its divisors is an integer number (178143560).

Almost surely, 2^1221400412 is an apocalyptic number.

It is an amenable number.

1221400412 is a deficient number, since it is larger than the sum of its proper divisors (916322308).

1221400412 is a wasteful number, since it uses less digits than its factorization.

1221400412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38860 (or 38858 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 1221400412 is about 34948.5394830743. The cubic root of 1221400412 is about 1068.9384213145.

Adding to 1221400412 its reverse (2140041221), we get a palindrome (3361441633).

The spelling of 1221400412 in words is "one billion, two hundred twenty-one million, four hundred thousand, four hundred twelve".