61520819 has 2 divisors, whose sum is σ = 61520820. Its totient is φ = 61520818.

The previous prime is 61520813. The next prime is 61520839. The reversal of 61520819 is 91802516.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61520819 - 2¹² = 61516723 is a prime.

It is a super-2 number, since 2×61520819² = 7569622340861522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61520813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30760409 + 30760410.

It is an arithmetic number, because the mean of its divisors is an integer number (30760410).

Almost surely, 2^61520819 is an apocalyptic number.

61520819 is a deficient number, since it is larger than the sum of its proper divisors (1).

61520819 is an equidigital number, since it uses as much as digits as its factorization.

61520819 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 61520819 is about 7843.5208293215. The cubic root of 61520819 is about 394.7668741349.

The spelling of 61520819 in words is "sixty-one million, five hundred twenty thousand, eight hundred nineteen".