681490 has 16 divisors (see below), whose sum is σ = 1280448. Its totient is φ = 260656.

The previous prime is 681487. The next prime is 681493. The reversal of 681490 is 94186.

It is an interprime number because it is at equal distance from previous prime (681487) and next prime (681493).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681493) 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, 1252 + ... + 1711.

It is an arithmetic number, because the mean of its divisors is an integer number (80028).

2⁶⁸¹⁴⁹⁰ is an apocalyptic number.

681490 is a deficient number, since it is larger than the sum of its proper divisors (598958).

681490 is a wasteful number, since it uses less digits than its factorization.

681490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2993.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 681490 is about 825.5240759663. The cubic root of 681490 is about 88.0007747866. Note that the first 3 decimals are identical.

The spelling of 681490 in words is "six hundred eighty-one thousand, four hundred ninety".