1291980500 has 48 divisors (see below), whose sum is σ = 2849193984. Its totient is φ = 511754400.

The previous prime is 1291980493. The next prime is 1291980511. The reversal of 1291980500 is 50891921.

It is a super-2 number, since 2×1291980500² = 3338427224760500000, 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 15 ways as a sum of consecutive naturals, for example, 38957 + ... + 64043.

It is an arithmetic number, because the mean of its divisors is an integer number (59358208).

Almost surely, 2^1291980500 is an apocalyptic number.

1291980500 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 1291980500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1424596992).

1291980500 is an abundant number, since it is smaller than the sum of its proper divisors (1557213484).

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

1291980500 is a wasteful number, since it uses less digits than its factorization.

1291980500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25209 (or 25197 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 1291980500 is about 35944.1302579434. The cubic root of 1291980500 is about 1089.1440408521.

The spelling of 1291980500 in words is "one billion, two hundred ninety-one million, nine hundred eighty thousand, five hundred".