1655501661 has 12 divisors (see below), whose sum is σ = 2608669440. Its totient is φ = 1003334280.

The previous prime is 1655501647. The next prime is 1655501663. The reversal of 1655501661 is 1661055561.

It is not a de Polignac number, because 1655501661 - 2¹⁸ = 1655239517 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1655501663) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8361021 + ... + 8361218.

It is an arithmetic number, because the mean of its divisors is an integer number (217389120).

Almost surely, 2^1655501661 is an apocalyptic number.

1655501661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1655501661 is a deficient number, since it is larger than the sum of its proper divisors (953167779).

1655501661 is a wasteful number, since it uses less digits than its factorization.

1655501661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16722256 (or 16722253 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

The square root of 1655501661 is about 40687.8564316185. The cubic root of 1655501661 is about 1182.9776518971.

The spelling of 1655501661 in words is "one billion, six hundred fifty-five million, five hundred one thousand, six hundred sixty-one".