1031386640 has 20 divisors (see below), whose sum is σ = 2397974124. Its totient is φ = 412554624.

The previous prime is 1031386613. The next prime is 1031386661. The reversal of 1031386640 is 466831301.

It can be written as a sum of positive squares in 2 ways, for example, as 478384384 + 553002256 = 21872^2 + 23516^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 1031386597 and 1031386606.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6446087 + ... + 6446246.

Almost surely, 2^1031386640 is an apocalyptic number.

1031386640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1031386640 is an abundant number, since it is smaller than the sum of its proper divisors (1366587484).

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

1031386640 is a wasteful number, since it uses less digits than its factorization.

1031386640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12892346 (or 12892340 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 1031386640 is about 32115.2088581096. The cubic root of 1031386640 is about 1010.3546250060.

The spelling of 1031386640 in words is "one billion, thirty-one million, three hundred eighty-six thousand, six hundred forty".