1561678394 has 8 divisors (see below), whose sum is σ = 2342698848. Its totient is φ = 780778780.

The previous prime is 1561678319. The next prime is 1561678409. The reversal of 1561678394 is 4938761651.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16619 + ... + 58305.

It is an arithmetic number, because the mean of its divisors is an integer number (292837356).

Almost surely, 2^1561678394 is an apocalyptic number.

1561678394 is a deficient number, since it is larger than the sum of its proper divisors (781020454).

1561678394 is a wasteful number, since it uses less digits than its factorization.

1561678394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60420.

The product of its digits is 1088640, while the sum is 50.

The square root of 1561678394 is about 39518.0768003707. The cubic root of 1561678394 is about 1160.1937830242.

The spelling of 1561678394 in words is "one billion, five hundred sixty-one million, six hundred seventy-eight thousand, three hundred ninety-four".