1220606391 has 8 divisors (see below), whose sum is σ = 1637841904. Its totient is φ = 808554240.

The previous prime is 1220606371. The next prime is 1220606393. The reversal of 1220606391 is 1936060221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1220606391 - 2⁹ = 1220605879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220606393) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1295290 + ... + 1296231.

It is an arithmetic number, because the mean of its divisors is an integer number (204730238).

Almost surely, 2^1220606391 is an apocalyptic number.

1220606391 is a deficient number, since it is larger than the sum of its proper divisors (417235513).

1220606391 is a wasteful number, since it uses less digits than its factorization.

1220606391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2591681.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 1220606391 is about 34937.1777766894. The cubic root of 1220606391 is about 1068.7067354737.

The spelling of 1220606391 in words is "one billion, two hundred twenty million, six hundred six thousand, three hundred ninety-one".