1561670 has 16 divisors (see below), whose sum is σ = 3066768. Its totient is φ = 567840.

The previous prime is 1561657. The next prime is 1561673. The reversal of 1561670 is 761651.

1561670 = T₂₉₁ + T₂₉₂ + ... + T₃₂₃.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6989 + ... + 7208.

It is an arithmetic number, because the mean of its divisors is an integer number (191673).

2^1561670 is an apocalyptic number.

1561670 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1561670 is a deficient number, since it is larger than the sum of its proper divisors (1505098).

1561670 is a wasteful number, since it uses less digits than its factorization.

1561670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14215.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 1561670 is about 1249.6679558987. The cubic root of 1561670 is about 116.0191704345.

The spelling of 1561670 in words is "one million, five hundred sixty-one thousand, six hundred seventy".