1561623464 has 8 divisors (see below), whose sum is σ = 2928044010. Its totient is φ = 780811728.

The previous prime is 1561623463. The next prime is 1561623473. The reversal of 1561623464 is 4643261651.

It can be written as a sum of positive squares in only one way, i.e., 888636100 + 672987364 = 29810^2 + 25942^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (1561623463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97601459 + ... + 97601474.

Almost surely, 2^1561623464 is an apocalyptic number.

It is an amenable number.

1561623464 is a deficient number, since it is larger than the sum of its proper divisors (1366420546).

1561623464 is a wasteful number, since it uses less digits than its factorization.

1561623464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195202939 (or 195202935 counting only the distinct ones).

The product of its digits is 103680, while the sum is 38.

The square root of 1561623464 is about 39517.3817958629. The cubic root of 1561623464 is about 1160.1801800972.

The spelling of 1561623464 in words is "one billion, five hundred sixty-one million, six hundred twenty-three thousand, four hundred sixty-four".