1561004411 has 12 divisors (see below), whose sum is σ = 1684482240. Its totient is φ = 1444953840.

The previous prime is 1561004407. The next prime is 1561004443. The reversal of 1561004411 is 1144001651.

It is a happy number.

It is not a de Polignac number, because 1561004411 - 2² = 1561004407 is a prime.

It is a super-2 number, since 2×1561004411² = 4873469542322913842, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1561004461) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31196 + ... + 63993.

It is an arithmetic number, because the mean of its divisors is an integer number (140373520).

Almost surely, 2^1561004411 is an apocalyptic number.

1561004411 is a deficient number, since it is larger than the sum of its proper divisors (123477829).

1561004411 is an equidigital number, since it uses as much as digits as its factorization.

1561004411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95266 (or 95243 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 1561004411 is about 39509.5483522654. The cubic root of 1561004411 is about 1160.0268550560.

The spelling of 1561004411 in words is "one billion, five hundred sixty-one million, four thousand, four hundred eleven".