1221601172 has 12 divisors (see below), whose sum is σ = 2332147776. Its totient is φ = 555273240.

The previous prime is 1221601123. The next prime is 1221601177. The reversal of 1221601172 is 2711061221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221601177) 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, 13881788 + ... + 13881875.

It is an arithmetic number, because the mean of its divisors is an integer number (194345648).

Almost surely, 2^1221601172 is an apocalyptic number.

It is an amenable number.

1221601172 is a deficient number, since it is larger than the sum of its proper divisors (1110546604).

1221601172 is a wasteful number, since it uses less digits than its factorization.

1221601172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27763678 (or 27763676 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 1221601172 is about 34951.4115880890. The cubic root of 1221601172 is about 1068.9969847795.

Adding to 1221601172 its reverse (2711061221), we get a palindrome (3932662393).

The spelling of 1221601172 in words is "one billion, two hundred twenty-one million, six hundred one thousand, one hundred seventy-two".