1661607 has 32 divisors (see below), whose sum is σ = 2688000. Its totient is φ = 1010880.

The previous prime is 1661599. The next prime is 1661623. The reversal of 1661607 is 7061661.

It is not a de Polignac number, because 1661607 - 2³ = 1661599 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661677) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20994 + ... + 21072.

It is an arithmetic number, because the mean of its divisors is an integer number (84000).

2^1661607 is an apocalyptic number.

1661607 is a deficient number, since it is larger than the sum of its proper divisors (1026393).

1661607 is a wasteful number, since it uses less digits than its factorization.

1661607 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 1661607 is about 1289.0333587615. The cubic root of 1661607 is about 118.4430105715.

The spelling of 1661607 in words is "one million, six hundred sixty-one thousand, six hundred seven".