690390851 has 4 divisors (see below), whose sum is σ = 691869672. Its totient is φ = 688912032.

The previous prime is 690390823. The next prime is 690390871. The reversal of 690390851 is 158093096.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 690390851 - 2⁶ = 690390787 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 690390799 and 690390808.

It is not an unprimeable number, because it can be changed into a prime (690390871) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 738710 + ... + 739643.

It is an arithmetic number, because the mean of its divisors is an integer number (172967418).

Almost surely, 2^690390851 is an apocalyptic number.

690390851 is a deficient number, since it is larger than the sum of its proper divisors (1478821).

690390851 is a wasteful number, since it uses less digits than its factorization.

690390851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1478820.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 690390851 is about 26275.2897415043. The cubic root of 690390851 is about 883.8224098632.

The spelling of 690390851 in words is "six hundred ninety million, three hundred ninety thousand, eight hundred fifty-one".