1561067377 has 2 divisors, whose sum is σ = 1561067378. Its totient is φ = 1561067376.

The previous prime is 1561067359. The next prime is 1561067383. The reversal of 1561067377 is 7737601651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1453820641 + 107246736 = 38129^2 + 10356^2 .

It is a cyclic number.

It is not a de Polignac number, because 1561067377 - 2²³ = 1552678769 is a prime.

It is not a weakly prime, because it can be changed into another prime (1561067327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780533688 + 780533689.

It is an arithmetic number, because the mean of its divisors is an integer number (780533689).

Almost surely, 2^1561067377 is an apocalyptic number.

It is an amenable number.

1561067377 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561067377 is an equidigital number, since it uses as much as digits as its factorization.

1561067377 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 185220, while the sum is 43.

The square root of 1561067377 is about 39510.3451895829. The cubic root of 1561067377 is about 1160.0424521226.

The spelling of 1561067377 in words is "one billion, five hundred sixty-one million, sixty-seven thousand, three hundred seventy-seven".