662009861 has 4 divisors (see below), whose sum is σ = 664926432. Its totient is φ = 659093292.

The previous prime is 662009849. The next prime is 662009863. The reversal of 662009861 is 168900266.

662009861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, and also an emirpimes, since its reverse is a distinct semiprime: 168900266 = 2 ⋅84450133.

It is a cyclic number.

It is not a de Polignac number, because 662009861 - 2²⁶ = 594900997 is a prime.

It is a super-2 number, since 2×662009861² = 876514112122478642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (662009863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1457945 + ... + 1458398.

It is an arithmetic number, because the mean of its divisors is an integer number (166231608).

Almost surely, 2^662009861 is an apocalyptic number.

It is an amenable number.

662009861 is a deficient number, since it is larger than the sum of its proper divisors (2916571).

662009861 is a wasteful number, since it uses less digits than its factorization.

662009861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2916570.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 662009861 is about 25729.5522891480. The cubic root of 662009861 is about 871.5416629605.

The spelling of 662009861 in words is "six hundred sixty-two million, nine thousand, eight hundred sixty-one".