1881720057 has 16 divisors (see below), whose sum is σ = 2959880192. Its totient is φ = 1040582160.

The previous prime is 1881720037. The next prime is 1881720067. The reversal of 1881720057 is 7500271881.

It is not a de Polignac number, because 1881720057 - 2¹¹ = 1881718009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1881719997 and 1881720024.

It is not an unprimeable number, because it can be changed into a prime (1881720017) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1444603 + ... + 1445904.

It is an arithmetic number, because the mean of its divisors is an integer number (184992512).

Almost surely, 2^1881720057 is an apocalyptic number.

It is an amenable number.

1881720057 is a deficient number, since it is larger than the sum of its proper divisors (1078160135).

1881720057 is a wasteful number, since it uses less digits than its factorization.

1881720057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2890548.

The product of its (nonzero) digits is 31360, while the sum is 39.

The square root of 1881720057 is about 43378.7973208110. The cubic root of 1881720057 is about 1234.5774438819.

The spelling of 1881720057 in words is "one billion, eight hundred eighty-one million, seven hundred twenty thousand, fifty-seven".