1561279478 has 16 divisors (see below), whose sum is σ = 2555886096. Its totient is φ = 709376640.

The previous prime is 1561279477. The next prime is 1561279481. The reversal of 1561279478 is 8749721651.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561279471) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44450 + ... + 71402.

It is an arithmetic number, because the mean of its divisors is an integer number (159742881).

Almost surely, 2^1561279478 is an apocalyptic number.

1561279478 is a deficient number, since it is larger than the sum of its proper divisors (994606618).

1561279478 is a wasteful number, since it uses less digits than its factorization.

1561279478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29599.

The product of its digits is 846720, while the sum is 50.

The square root of 1561279478 is about 39513.0292182212. The cubic root of 1561279478 is about 1160.0949877626.

The spelling of 1561279478 in words is "one billion, five hundred sixty-one million, two hundred seventy-nine thousand, four hundred seventy-eight".