61651550999 has 2 divisors, whose sum is σ = 61651551000. Its totient is φ = 61651550998.

The previous prime is 61651550971. The next prime is 61651551023. The reversal of 61651550999 is 99905515616.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61651550999 - 2¹² = 61651546903 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61651550929) 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, 30825775499 + 30825775500.

It is an arithmetic number, because the mean of its divisors is an integer number (30825775500).

Almost surely, 2^61651550999 is an apocalyptic number.

61651550999 is a deficient number, since it is larger than the sum of its proper divisors (1).

61651550999 is an equidigital number, since it uses as much as digits as its factorization.

61651550999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3280500, while the sum is 56.

The spelling of 61651550999 in words is "sixty-one billion, six hundred fifty-one million, five hundred fifty thousand, nine hundred ninety-nine".