1961669209751 has 2 divisors, whose sum is σ = 1961669209752. Its totient is φ = 1961669209750.

The previous prime is 1961669209727. The next prime is 1961669209763. The reversal of 1961669209751 is 1579029661691.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1961669209751 is a prime.

It is a super-2 number, since 2×1961669209751² (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 (1961669209711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 980834604875 + 980834604876.

It is an arithmetic number, because the mean of its divisors is an integer number (980834604876).

Almost surely, 2^{1961669209751} is an apocalyptic number.

1961669209751 is a deficient number, since it is larger than the sum of its proper divisors (1).

1961669209751 is an equidigital number, since it uses as much as digits as its factorization.

1961669209751 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11022480, while the sum is 62.

The spelling of 1961669209751 in words is "one trillion, nine hundred sixty-one billion, six hundred sixty-nine million, two hundred nine thousand, seven hundred fifty-one".