61551512069 has 2 divisors, whose sum is σ = 61551512070. Its totient is φ = 61551512068.

The previous prime is 61551512021. The next prime is 61551512129. The reversal of 61551512069 is 96021515516.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60879147169 + 672364900 = 246737^2 + 25930^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61551512069 is a prime.

It is a super-2 number, since 2×61551512069² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61551512569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30775756034 + 30775756035.

It is an arithmetic number, because the mean of its divisors is an integer number (30775756035).

Almost surely, 2^61551512069 is an apocalyptic number.

It is an amenable number.

61551512069 is a deficient number, since it is larger than the sum of its proper divisors (1).

61551512069 is an equidigital number, since it uses as much as digits as its factorization.

61551512069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81000, while the sum is 41.

The spelling of 61551512069 in words is "sixty-one billion, five hundred fifty-one million, five hundred twelve thousand, sixty-nine".