1721012040 has 144 divisors (see below), whose sum is σ = 6148151100. Its totient is φ = 417204480.

The previous prime is 1721011997. The next prime is 1721012057. The reversal of 1721012040 is 402101271.

It can be written as a sum of positive squares in 2 ways, for example, as 1636849764 + 84162276 = 40458^2 + 9174^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 23806 + ... + 63314.

Almost surely, 2^1721012040 is an apocalyptic number.

1721012040 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 1721012040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3074075550).

1721012040 is an abundant number, since it is smaller than the sum of its proper divisors (4427139060).

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

1721012040 is a wasteful number, since it uses less digits than its factorization.

1721012040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39548 (or 39530 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 1721012040 is about 41485.0821380409. The cubic root of 1721012040 is about 1198.3802312748.

The spelling of 1721012040 in words is "one billion, seven hundred twenty-one million, twelve thousand, forty".