661055051 has 2 divisors, whose sum is σ = 661055052. Its totient is φ = 661055050.

The previous prime is 661055041. The next prime is 661055107. The reversal of 661055051 is 150550166.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661055051 is a prime.

It is a super-2 number, since 2×661055051² = 873987560905225202, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (661055041) 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, 330527525 + 330527526.

It is an arithmetic number, because the mean of its divisors is an integer number (330527526).

Almost surely, 2^661055051 is an apocalyptic number.

661055051 is a deficient number, since it is larger than the sum of its proper divisors (1).

661055051 is an equidigital number, since it uses as much as digits as its factorization.

661055051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4500, while the sum is 29.

The square root of 661055051 is about 25710.9908599416. The cubic root of 661055051 is about 871.1224561705.

The spelling of 661055051 in words is "six hundred sixty-one million, fifty-five thousand, fifty-one".