1630861 has 16 divisors (see below), whose sum is σ = 1862784. Its totient is φ = 1419264.

The previous prime is 1630859. The next prime is 1630891. The reversal of 1630861 is 1680361.

It is a 6-Lehmer number, since φ(1630861) divides (1630861-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 1630861 - 2¹ = 1630859 is a prime.

It is a Duffinian number.

1630861 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1630801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16765 + ... + 16861.

It is an arithmetic number, because the mean of its divisors is an integer number (116424).

2^1630861 is an apocalyptic number.

It is an amenable number.

1630861 is a deficient number, since it is larger than the sum of its proper divisors (231923).

1630861 is a wasteful number, since it uses less digits than its factorization.

1630861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 1630861 is about 1277.0516825877. The cubic root of 1630861 is about 117.7079101524.

The spelling of 1630861 in words is "one million, six hundred thirty thousand, eight hundred sixty-one".