1655116221 has 8 divisors (see below), whose sum is σ = 2407441824. Its totient is φ = 1003100720.

The previous prime is 1655116207. The next prime is 1655116223. The reversal of 1655116221 is 1226115561.

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

It is a cyclic number.

It is not a de Polignac number, because 1655116221 - 2⁶ = 1655116157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1655116223) 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, 25077486 + ... + 25077551.

It is an arithmetic number, because the mean of its divisors is an integer number (300930228).

Almost surely, 2^1655116221 is an apocalyptic number.

1655116221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1655116221 is a deficient number, since it is larger than the sum of its proper divisors (752325603).

1655116221 is a wasteful number, since it uses less digits than its factorization.

1655116221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50155051.

The product of its digits is 3600, while the sum is 30.

The square root of 1655116221 is about 40683.1196075227. The cubic root of 1655116221 is about 1182.8858363651.

The spelling of 1655116221 in words is "one billion, six hundred fifty-five million, one hundred sixteen thousand, two hundred twenty-one".