1561262668 has 24 divisors (see below), whose sum is σ = 3131492000. Its totient is φ = 667191168.

The previous prime is 1561262663. The next prime is 1561262669. The reversal of 1561262668 is 8662621651.

It is a super-2 number, since 2×1561262668² = 4875082236980956448, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1561262663) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 70113 + ... + 89656.

Almost surely, 2^1561262668 is an apocalyptic number.

It is an amenable number.

1561262668 is an abundant number, since it is smaller than the sum of its proper divisors (1570229332).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1561262668 is a wasteful number, since it uses less digits than its factorization.

1561262668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160129 (or 160127 counting only the distinct ones).

The product of its digits is 207360, while the sum is 43.

The square root of 1561262668 is about 39512.8165030032. The cubic root of 1561262668 is about 1160.0908242401.

The spelling of 1561262668 in words is "one billion, five hundred sixty-one million, two hundred sixty-two thousand, six hundred sixty-eight".