1001009880 has 256 divisors, whose sum is σ = 3640896000. Its totient is φ = 243150336.

The previous prime is 1001009879. The next prime is 1001009899. The reversal of 1001009880 is 889001001.

It is a super-2 number, since 2×1001009880² = 2004041559715228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1164891 + ... + 1165749.

It is an arithmetic number, because the mean of its divisors is an integer number (14222250).

Almost surely, 2^1001009880 is an apocalyptic number.

1001009880 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 1001009880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1820448000).

1001009880 is an abundant number, since it is smaller than the sum of its proper divisors (2639886120).

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

1001009880 is a wasteful number, since it uses less digits than its factorization.

1001009880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 975 (or 965 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 1001009880 is about 31638.7401771942. The cubic root of 1001009880 is about 1000.3365134127.

The spelling of 1001009880 in words is "one billion, one million, nine thousand, eight hundred eighty".