1221922905 has 32 divisors (see below), whose sum is σ = 2237470464. Its totient is φ = 557819136.

The previous prime is 1221922883. The next prime is 1221922921. The reversal of 1221922905 is 5092291221.

It is not a de Polignac number, because 1221922905 - 2⁶ = 1221922841 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 71799 + ... + 87171.

It is an arithmetic number, because the mean of its divisors is an integer number (69920952).

Almost surely, 2^1221922905 is an apocalyptic number.

1221922905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1221922905 is a deficient number, since it is larger than the sum of its proper divisors (1015547559).

1221922905 is a wasteful number, since it uses less digits than its factorization.

1221922905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16145.

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 1221922905 is about 34956.0138602787. The cubic root of 1221922905 is about 1069.0908237578.

The spelling of 1221922905 in words is "one billion, two hundred twenty-one million, nine hundred twenty-two thousand, nine hundred five".