2001721515510 has 64 divisors (see below), whose sum is σ = 4901099438592. Its totient is φ = 523100768256.

The previous prime is 2001721515503. The next prime is 2001721515511. The reversal of 2001721515510 is 155151271002.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001721515511) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2192074 + ... + 2967933.

It is an arithmetic number, because the mean of its divisors is an integer number (76579678728).

Almost surely, 2^{2001721515510} is an apocalyptic number.

2001721515510 is an abundant number, since it is smaller than the sum of its proper divisors (2899377923082).

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

2001721515510 is a wasteful number, since it uses less digits than its factorization.

2001721515510 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5160277.

The product of its (nonzero) digits is 3500, while the sum is 30.

Adding to 2001721515510 its reverse (155151271002), we get a palindrome (2156872786512).

The spelling of 2001721515510 in words is "two trillion, one billion, seven hundred twenty-one million, five hundred fifteen thousand, five hundred ten".