6121720505 has 16 divisors (see below), whose sum is σ = 7686925824. Its totient is φ = 4674464640.

The previous prime is 6121720483. The next prime is 6121720511. The reversal of 6121720505 is 5050271216.

It is not a de Polignac number, because 6121720505 - 2⁶ = 6121720441 is a prime.

It is a Duffinian 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, 259199 + ... + 281828.

It is an arithmetic number, because the mean of its divisors is an integer number (480432864).

Almost surely, 2^6121720505 is an apocalyptic number.

It is an amenable number.

6121720505 is a deficient number, since it is larger than the sum of its proper divisors (1565205319).

6121720505 is a wasteful number, since it uses less digits than its factorization.

6121720505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541136.

The product of its (nonzero) digits is 4200, while the sum is 29.

The square root of 6121720505 is about 78241.4244821757. The cubic root of 6121720505 is about 1829.3262477394.

Subtracting from 6121720505 its reverse (5050271216), we obtain a square (1071449289 = 32733²).

The spelling of 6121720505 in words is "six billion, one hundred twenty-one million, seven hundred twenty thousand, five hundred five".