1630904 has 32 divisors (see below), whose sum is σ = 3421440. Its totient is φ = 722400.

The previous prime is 1630897. The next prime is 1630913. The reversal of 1630904 is 4090361.

It is a Smith number, since the sum of its digits (23) coincides with the sum of the digits of its prime factors.

It is an Ulam number.

It is a plaindrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 1630904.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3569 + ... + 3999.

It is an arithmetic number, because the mean of its divisors is an integer number (106920).

2^1630904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1630904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1710720).

1630904 is an abundant number, since it is smaller than the sum of its proper divisors (1790536).

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

1630904 is a wasteful number, since it uses less digits than its factorization.

1630904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491 (or 487 counting only the distinct ones).

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

The square root of 1630904 is about 1277.0685181305. The cubic root of 1630904 is about 117.7089446562.

The spelling of 1630904 in words is "one million, six hundred thirty thousand, nine hundred four".