1561455069 has 4 divisors (see below), whose sum is σ = 2081940096. Its totient is φ = 1040970044.

The previous prime is 1561455059. The next prime is 1561455079. The reversal of 1561455069 is 9605541651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9605541651 = 3 ⋅3201847217.

It is an interprime number because it is at equal distance from previous prime (1561455059) and next prime (1561455079).

It is a cyclic number.

It is not a de Polignac number, because 1561455069 - 2⁴ = 1561455053 is a prime.

It is a super-2 number, since 2×1561455069² = 4876283865011589522, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1561455069.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561455059) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 260242509 + ... + 260242514.

It is an arithmetic number, because the mean of its divisors is an integer number (520485024).

Almost surely, 2^1561455069 is an apocalyptic number.

It is an amenable number.

1561455069 is a deficient number, since it is larger than the sum of its proper divisors (520485027).

1561455069 is an equidigital number, since it uses as much as digits as its factorization.

1561455069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520485026.

The product of its (nonzero) digits is 162000, while the sum is 42.

The square root of 1561455069 is about 39515.2510937233. The cubic root of 1561455069 is about 1160.1384765819.

The spelling of 1561455069 in words is "one billion, five hundred sixty-one million, four hundred fifty-five thousand, sixty-nine".