61815356441 has 2 divisors, whose sum is σ = 61815356442. Its totient is φ = 61815356440.

The previous prime is 61815356437. The next prime is 61815356459. The reversal of 61815356441 is 14465351816.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52424971225 + 9390385216 = 228965^2 + 96904^2 .

It is a cyclic number.

It is not a de Polignac number, because 61815356441 - 2² = 61815356437 is a prime.

It is a super-2 number, since 2×61815356441² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 61815356392 and 61815356401.

It is not a weakly prime, because it can be changed into another prime (61815316441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30907678220 + 30907678221.

It is an arithmetic number, because the mean of its divisors is an integer number (30907678221).

Almost surely, 2^61815356441 is an apocalyptic number.

It is an amenable number.

61815356441 is a deficient number, since it is larger than the sum of its proper divisors (1).

61815356441 is an equidigital number, since it uses as much as digits as its factorization.

61815356441 is an evil number, because the sum of its binary digits is even.

The product of its digits is 345600, while the sum is 44.

The spelling of 61815356441 in words is "sixty-one billion, eight hundred fifteen million, three hundred fifty-six thousand, four hundred forty-one".