1661516051 has 16 divisors (see below), whose sum is σ = 1826949600. Its totient is φ = 1501667328.

The previous prime is 1661516041. The next prime is 1661516069. The reversal of 1661516051 is 1506151661.

It is a cyclic number.

It is not a de Polignac number, because 1661516051 - 2¹⁰ = 1661515027 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1661515999 and 1661516017.

It is not an unprimeable number, because it can be changed into a prime (1661516041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 192905 + ... + 201333.

It is an arithmetic number, because the mean of its divisors is an integer number (114184350).

Almost surely, 2^1661516051 is an apocalyptic number.

1661516051 is a deficient number, since it is larger than the sum of its proper divisors (165433549).

1661516051 is a wasteful number, since it uses less digits than its factorization.

1661516051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8758.

The product of its (nonzero) digits is 5400, while the sum is 32.

The square root of 1661516051 is about 40761.6983331166. The cubic root of 1661516051 is about 1184.4084951701.

The spelling of 1661516051 in words is "one billion, six hundred sixty-one million, five hundred sixteen thousand, fifty-one".