1261746540 has 72 divisors (see below), whose sum is σ = 3865247568. Its totient is φ = 333129600.

The previous prime is 1261746539. The next prime is 1261746553. The reversal of 1261746540 is 456471621.

1261746540 is a `hidden beast` number, since 12 + 61 + 7 + 46 + 540 = 666.

1261746540 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1261746495 and 1261746504.

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, 16522 + ... + 52881.

It is an arithmetic number, because the mean of its divisors is an integer number (53683994).

Almost surely, 2^1261746540 is an apocalyptic number.

1261746540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1261746540 is an abundant number, since it is smaller than the sum of its proper divisors (2603501028).

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

1261746540 is a wasteful number, since it uses less digits than its factorization.

1261746540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69519 (or 69514 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 1261746540 is about 35521.0717743708. The cubic root of 1261746540 is about 1080.5811173024.

The spelling of 1261746540 in words is "one billion, two hundred sixty-one million, seven hundred forty-six thousand, five hundred forty".