1161987540 has 48 divisors (see below), whose sum is σ = 3718361472. Its totient is φ = 265597056.

The previous prime is 1161987511. The next prime is 1161987571. The reversal of 1161987540 is 457891611.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1161987492 and 1161987501.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1382899 + ... + 1383738.

It is an arithmetic number, because the mean of its divisors is an integer number (77465864).

Almost surely, 2^1161987540 is an apocalyptic number.

1161987540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1161987540 is an abundant number, since it is smaller than the sum of its proper divisors (2556373932).

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

1161987540 is a wasteful number, since it uses less digits than its factorization.

1161987540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2766656 (or 2766654 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 42.

The square root of 1161987540 is about 34087.9383360156. The cubic root of 1161987540 is about 1051.3173307118.

The spelling of 1161987540 in words is "one billion, one hundred sixty-one million, nine hundred eighty-seven thousand, five hundred forty".