1292785920 has 360 divisors, whose sum is σ = 4764944184. Its totient is φ = 334430208.

The previous prime is 1292785891. The next prime is 1292785931. The reversal of 1292785920 is 295872921.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 224280576 + 1068505344 = 14976^2 + 32688^2 .

It is a tau number, because it is divible by the number of its divisors (360).

It is a super-3 number, since 3×1292785920³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 3835992 + ... + 3836328.

Almost surely, 2^1292785920 is an apocalyptic number.

1292785920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1292785920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2382472092).

1292785920 is an abundant number, since it is smaller than the sum of its proper divisors (3472158264).

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

1292785920 is an equidigital number, since it uses as much as digits as its factorization.

1292785920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407 (or 384 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The square root of 1292785920 is about 35955.3322888275. The cubic root of 1292785920 is about 1089.3703177891.

The spelling of 1292785920 in words is "one billion, two hundred ninety-two million, seven hundred eighty-five thousand, nine hundred twenty".