240265648561 has 3 divisors (see below), whose sum is σ = 240266138731. Its totient is φ = 240265158392.

The previous prime is 240265648541. The next prime is 240265648577. The reversal of 240265648561 is 165846562042.

It is a happy number.

The square root of 240265648561 is 490169.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 239934408561 + 331240000 = 489831^2 + 18200^2 .

It is not a de Polignac number, because 240265648561 - 2¹³ = 240265640369 is a prime.

It is a super-2 number, since 2×240265648561² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (240265648541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 245085 + ... + 735253.

Almost surely, 2^240265648561 is an apocalyptic number.

240265648561 is the 490169-th square number.

240265648561 is the 245085-th centered octagonal number.

It is an amenable number.

240265648561 is a deficient number, since it is larger than the sum of its proper divisors (490170).

240265648561 is an frugal number, since it uses more digits than its factorization.

240265648561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 980338 (or 490169 counting only the distinct ones).

The product of its (nonzero) digits is 2764800, while the sum is 49.

Multiplying 240265648561 by its sum of digits (49), we get a square (11773016779489 = 3431183²).

The spelling of 240265648561 in words is "two hundred forty billion, two hundred sixty-five million, six hundred forty-eight thousand, five hundred sixty-one".