61425210625661 has 2 divisors, whose sum is σ = 61425210625662. Its totient is φ = 61425210625660.

The previous prime is 61425210625651. The next prime is 61425210625729. The reversal of 61425210625661 is 16652601252416.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61374391940761 + 50818684900 = 7834181^2 + 225430^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61425210625661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61425210625601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30712605312830 + 30712605312831.

It is an arithmetic number, because the mean of its divisors is an integer number (30712605312831).

Almost surely, 2^{61425210625661} is an apocalyptic number.

It is an amenable number.

61425210625661 is a deficient number, since it is larger than the sum of its proper divisors (1).

61425210625661 is an equidigital number, since it uses as much as digits as its factorization.

61425210625661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1036800, while the sum is 47.

The spelling of 61425210625661 in words is "sixty-one trillion, four hundred twenty-five billion, two hundred ten million, six hundred twenty-five thousand, six hundred sixty-one".