1661006550 has 48 divisors (see below), whose sum is σ = 4707770112. Its totient is φ = 379658400.

The previous prime is 1661006507. The next prime is 1661006569. The reversal of 1661006550 is 556001661.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 789906 + ... + 792005.

It is an arithmetic number, because the mean of its divisors is an integer number (98078544).

Almost surely, 2^1661006550 is an apocalyptic number.

1661006550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1661006550 is an abundant number, since it is smaller than the sum of its proper divisors (3046763562).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661006550 is a wasteful number, since it uses less digits than its factorization.

1661006550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1581933 (or 1581928 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 1661006550 is about 40755.4481020636. The cubic root of 1661006550 is about 1184.2874171932.

The spelling of 1661006550 in words is "one billion, six hundred sixty-one million, six thousand, five hundred fifty".