1661630 has 16 divisors (see below), whose sum is σ = 3026160. Its totient is φ = 656832.

The previous prime is 1661629. The next prime is 1661641. The reversal of 1661630 is 361661.

It is a super-2 number, since 2×1661630² = 5522028513800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1661596 and 1661605.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44 + ... + 1823.

It is an arithmetic number, because the mean of its divisors is an integer number (189135).

2^1661630 is an apocalyptic number.

1661630 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1661630 is a deficient number, since it is larger than the sum of its proper divisors (1364530).

1661630 is a wasteful number, since it uses less digits than its factorization.

1661630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1963.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 1661630 is about 1289.0422801444. The cubic root of 1661630 is about 118.4435570659.

The spelling of 1661630 in words is "one million, six hundred sixty-one thousand, six hundred thirty".