1720021215040 has 56 divisors (see below), whose sum is σ = 4097074566312. Its totient is φ = 687794472960.

The previous prime is 1720021215007. The next prime is 1720021215041. The reversal of 1720021215040 is 405121200271.

It can be written as a sum of positive squares in 4 ways, for example, as 23817131584 + 1696204083456 = 154328^2 + 1302384^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1720021214996 and 1720021215014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1720021215041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 196342 + ... + 1865098.

It is an arithmetic number, because the mean of its divisors is an integer number (73162045827).

Almost surely, 2^{1720021215040} is an apocalyptic number.

1720021215040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1720021215040 is an abundant number, since it is smaller than the sum of its proper divisors (2377053351272).

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

1720021215040 is a wasteful number, since it uses less digits than its factorization.

1720021215040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1671995 (or 1671985 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The spelling of 1720021215040 in words is "one trillion, seven hundred twenty billion, twenty-one million, two hundred fifteen thousand, forty".