1001785801 has 9 divisors (see below), whose sum is σ = 1036158759. Its totient is φ = 968520600.

The previous prime is 1001785787. The next prime is 1001785867. The reversal of 1001785801 is 1085871001.

The square root of 1001785801 is 31651.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 583174201 + 418611600 = 24149^2 + 20460^2 .

It is not a de Polignac number, because 1001785801 - 2⁹ = 1001785289 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1001785201) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 980671 + ... + 981691.

It is an arithmetic number, because the mean of its divisors is an integer number (115128751).

Almost surely, 2^1001785801 is an apocalyptic number.

1001785801 is the 31651-st square number.

1001785801 is the 15826-th centered octagonal number.

It is an amenable number.

1001785801 is a deficient number, since it is larger than the sum of its proper divisors (34372958).

1001785801 is an frugal number, since it uses more digits than its factorization.

1001785801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2104 (or 1052 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 31.

The cubic root of 1001785801 is about 1000.5949130083.

The spelling of 1001785801 in words is "one billion, one million, seven hundred eighty-five thousand, eight hundred one".