289242640 has 40 divisors (see below), whose sum is σ = 681974208. Its totient is φ = 114065280.

The previous prime is 289242637. The next prime is 289242671. The reversal of 289242640 is 46242982.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×289242640² = 167322609588339200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 289242640.

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, 19782 + ... + 31141.

Almost surely, 2^289242640 is an apocalyptic number.

289242640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

289242640 is an abundant number, since it is smaller than the sum of its proper divisors (392731568).

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

289242640 is a wasteful number, since it uses less digits than its factorization.

289242640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51007 (or 51001 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 37.

The square root of 289242640 is about 17007.1349732987. The cubic root of 289242640 is about 661.3338802711. Note that the first 3 decimals are identical.

The spelling of 289242640 in words is "two hundred eighty-nine million, two hundred forty-two thousand, six hundred forty".