1213131440 has 40 divisors (see below), whose sum is σ = 2822350608. Its totient is φ = 484939520.

The previous prime is 1213131431. The next prime is 1213131497. The reversal of 1213131440 is 441313121.

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, 150554 + ... + 158406.

Almost surely, 2^1213131440 is an apocalyptic number.

1213131440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1213131440 is an abundant number, since it is smaller than the sum of its proper divisors (1609219168).

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

1213131440 is a wasteful number, since it uses less digits than its factorization.

1213131440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9797 (or 9791 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 1213131440 is about 34830.0364628003. The cubic root of 1213131440 is about 1066.5206926979.

Adding to 1213131440 its reverse (441313121), we get a palindrome (1654444561).

The spelling of 1213131440 in words is "one billion, two hundred thirteen million, one hundred thirty-one thousand, four hundred forty".