249206640 has 60 divisors (see below), whose sum is σ = 773299464. Its totient is φ = 66389888.

The previous prime is 249206561. The next prime is 249206647. The reversal of 249206640 is 46602942.

249206640 = T₁₂₅ + T₁₂₆ + ... + T₁₁₄₃.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (60).

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249206647) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 244051 + ... + 245069.

Almost surely, 2^249206640 is an apocalyptic number.

249206640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

249206640 is an abundant number, since it is smaller than the sum of its proper divisors (524092824).

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

249206640 is an equidigital number, since it uses as much as digits as its factorization.

249206640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2054 (or 1029 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 249206640 is about 15786.2801191414. The cubic root of 249206640 is about 629.2934381529.

The spelling of 249206640 in words is "two hundred forty-nine million, two hundred six thousand, six hundred forty".