1561672669057 has 4 divisors (see below), whose sum is σ = 1561678406080. Its totient is φ = 1561666932036.

The previous prime is 1561672668991. The next prime is 1561672669069. The reversal of 1561672669057 is 7509662761651.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 1561672669057 - 2⁷ = 1561672668929 is a prime.

It is a super-2 number, since 2×1561672669057² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1561672668986 and 1561672669004.

It is not an unprimeable number, because it can be changed into a prime (1561672669357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2438733 + ... + 3011770.

It is an arithmetic number, because the mean of its divisors is an integer number (390419601520).

Almost surely, 2^{1561672669057} is an apocalyptic number.

It is an amenable number.

1561672669057 is a deficient number, since it is larger than the sum of its proper divisors (5737023).

1561672669057 is an equidigital number, since it uses as much as digits as its factorization.

1561672669057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5737022.

The product of its (nonzero) digits is 28576800, while the sum is 61.

The spelling of 1561672669057 in words is "one trillion, five hundred sixty-one billion, six hundred seventy-two million, six hundred sixty-nine thousand, fifty-seven".