1221030906 has 16 divisors (see below), whose sum is σ = 2526271200. Its totient is φ = 392975408.

The previous prime is 1221030893. The next prime is 1221030911. The reversal of 1221030906 is 6090301221.

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, 3508536 + ... + 3508883.

It is an arithmetic number, because the mean of its divisors is an integer number (157891950).

Almost surely, 2^1221030906 is an apocalyptic number.

1221030906 is an abundant number, since it is smaller than the sum of its proper divisors (1305240294).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221030906 is a wasteful number, since it uses less digits than its factorization.

1221030906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7017453.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 1221030906 is about 34943.2526534094. The cubic root of 1221030906 is about 1068.8306163737.

The spelling of 1221030906 in words is "one billion, two hundred twenty-one million, thirty thousand, nine hundred six".