1561969142 has 8 divisors (see below), whose sum is σ = 2392803936. Its totient is φ = 764367832.

The previous prime is 1561969139. The next prime is 1561969153. The reversal of 1561969142 is 2419691651.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 1561969093 and 1561969102.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 8308253 + ... + 8308440.

It is an arithmetic number, because the mean of its divisors is an integer number (299100492).

Almost surely, 2^1561969142 is an apocalyptic number.

1561969142 is a deficient number, since it is larger than the sum of its proper divisors (830834794).

1561969142 is a wasteful number, since it uses less digits than its factorization.

1561969142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16616742.

The product of its digits is 116640, while the sum is 44.

The square root of 1561969142 is about 39521.7553000876. The cubic root of 1561969142 is about 1160.2657788742.

The spelling of 1561969142 in words is "one billion, five hundred sixty-one million, nine hundred sixty-nine thousand, one hundred forty-two".