1231020440 has 32 divisors (see below), whose sum is σ = 2982858480. Its totient is φ = 454530432.

The previous prime is 1231020397. The next prime is 1231020457. The reversal of 1231020440 is 440201321.

It is a super-2 number, since 2×1231020440² = 3030822647395587200, which contains 22 as substring.

It is a congruent number.

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, 1183154 + ... + 1184193.

Almost surely, 2^1231020440 is an apocalyptic number.

1231020440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1231020440 is an abundant number, since it is smaller than the sum of its proper divisors (1751838040).

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

1231020440 is a wasteful number, since it uses less digits than its factorization.

1231020440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2367371 (or 2367367 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 1231020440 is about 35085.9008720027. The cubic root of 1231020440 is about 1071.7374863069.

Adding to 1231020440 its reverse (440201321), we get a palindrome (1671221761).

The spelling of 1231020440 in words is "one billion, two hundred thirty-one million, twenty thousand, four hundred forty".