1011531440 has 40 divisors (see below), whose sum is σ = 2361009600. Its totient is φ = 403030016.

The previous prime is 1011531439. The next prime is 1011531461. The reversal of 1011531440 is 441351101.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4040 + ... + 45159.

It is an arithmetic number, because the mean of its divisors is an integer number (59025240).

Almost surely, 2^1011531440 is an apocalyptic number.

1011531440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1011531440 is an abundant number, since it is smaller than the sum of its proper divisors (1349478160).

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

1011531440 is a wasteful number, since it uses less digits than its factorization.

1011531440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49469 (or 49463 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 1011531440 is about 31804.5820598228. The cubic root of 1011531440 is about 1003.8291323641.

Adding to 1011531440 its reverse (441351101), we get a palindrome (1452882541).

The spelling of 1011531440 in words is "one billion, eleven million, five hundred thirty-one thousand, four hundred forty".