1655891013961 has 2 divisors, whose sum is σ = 1655891013962. Its totient is φ = 1655891013960.

The previous prime is 1655891013949. The next prime is 1655891014081. The reversal of 1655891013961 is 1693101985561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1655162013961 + 729000000 = 1286531^2 + 27000^2 .

It is a cyclic number.

It is not a de Polignac number, because 1655891013961 - 2⁹ = 1655891013449 is a prime.

It is not a weakly prime, because it can be changed into another prime (1655891017961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 827945506980 + 827945506981.

It is an arithmetic number, because the mean of its divisors is an integer number (827945506981).

Almost surely, 2^{1655891013961} is an apocalyptic number.

It is an amenable number.

1655891013961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1655891013961 is an equidigital number, since it uses as much as digits as its factorization.

1655891013961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1749600, while the sum is 55.

The spelling of 1655891013961 in words is "one trillion, six hundred fifty-five billion, eight hundred ninety-one million, thirteen thousand, nine hundred sixty-one".