690571890 has 48 divisors (see below), whose sum is σ = 1796909400. Its totient is φ = 184006656.

The previous prime is 690571883. The next prime is 690571913. The reversal of 690571890 is 98175096.

It can be written as a sum of positive squares in 4 ways, for example, as 686073249 + 4498641 = 26193^2 + 2121^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 158866 + ... + 163154.

Almost surely, 2^690571890 is an apocalyptic number.

690571890 is an abundant number, since it is smaller than the sum of its proper divisors (1106337510).

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

690571890 is a wasteful number, since it uses less digits than its factorization.

690571890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6091 (or 6088 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 45.

The square root of 690571890 is about 26278.7345585742. The cubic root of 690571890 is about 883.8996570926.

The spelling of 690571890 in words is "six hundred ninety million, five hundred seventy-one thousand, eight hundred ninety".