1720450644 has 48 divisors (see below), whose sum is σ = 4401625536. Its totient is φ = 518694400.

The previous prime is 1720450619. The next prime is 1720450661. The reversal of 1720450644 is 4460540271.

It is a Harshad number since it is a multiple of its sum of digits (33).

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, 7077 + ... + 59084.

It is an arithmetic number, because the mean of its divisors is an integer number (91700532).

Almost surely, 2^1720450644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1720450644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2200812768).

1720450644 is an abundant number, since it is smaller than the sum of its proper divisors (2681174892).

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

1720450644 is a wasteful number, since it uses less digits than its factorization.

1720450644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66376 (or 66374 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 33.

The square root of 1720450644 is about 41478.3153466965. The cubic root of 1720450644 is about 1198.2499127920.

The spelling of 1720450644 in words is "one billion, seven hundred twenty million, four hundred fifty thousand, six hundred forty-four".