1659961 has 8 divisors (see below), whose sum is σ = 1703240. Its totient is φ = 1617408.

The previous prime is 1659919. The next prime is 1659971. The reversal of 1659961 is 1699561.

It can be written as a sum of positive squares in 4 ways, for example, as 207936 + 1452025 = 456^2 + 1205^2 .

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 1659961 - 2¹⁵ = 1627193 is a prime.

It is a Duffinian number.

1659961 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1659961.

It is not an unprimeable number, because it can be changed into a prime (1659971) 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, 10495 + ... + 10651.

It is an arithmetic number, because the mean of its divisors is an integer number (212905).

2^1659961 is an apocalyptic number.

It is an amenable number.

1659961 is a deficient number, since it is larger than the sum of its proper divisors (43279).

1659961 is a wasteful number, since it uses less digits than its factorization.

1659961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363.

The product of its digits is 14580, while the sum is 37.

The square root of 1659961 is about 1288.3947376484. The cubic root of 1659961 is about 118.4038874804.

The spelling of 1659961 in words is "one million, six hundred fifty-nine thousand, nine hundred sixty-one".