1928291101981 has 2 divisors, whose sum is σ = 1928291101982. Its totient is φ = 1928291101980.

The previous prime is 1928291101937. The next prime is 1928291102027. The reversal of 1928291101981 is 1891011928291.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1855125720900 + 73165381081 = 1362030^2 + 270491^2 .

It is a cyclic number.

It is not a de Polignac number, because 1928291101981 - 2⁹ = 1928291101469 is a prime.

It is a super-2 number, since 2×1928291101981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1928291101921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 964145550990 + 964145550991.

It is an arithmetic number, because the mean of its divisors is an integer number (964145550991).

Almost surely, 2^{1928291101981} is an apocalyptic number.

It is an amenable number.

1928291101981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1928291101981 is an equidigital number, since it uses as much as digits as its factorization.

1928291101981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 52.

The spelling of 1928291101981 in words is "one trillion, nine hundred twenty-eight billion, two hundred ninety-one million, one hundred one thousand, nine hundred eighty-one".