261963662040 has 96 divisors (see below), whose sum is σ = 896191498800. Its totient is φ = 66180291840.

The previous prime is 261963662029. The next prime is 261963662057. The reversal of 261963662040 is 40266369162.

261963662040 is a `hidden beast` number, since 2 + 6 + 1 + 9 + 636 + 6 + 2 + 0 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19142551 + ... + 19156230.

Almost surely, 2^261963662040 is an apocalyptic number.

261963662040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261963662040 is an abundant number, since it is smaller than the sum of its proper divisors (634227836760).

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

261963662040 is a wasteful number, since it uses less digits than its factorization.

261963662040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38298817 (or 38298810 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 45.

The spelling of 261963662040 in words is "two hundred sixty-one billion, nine hundred sixty-three million, six hundred sixty-two thousand, forty".