646623031 has 4 divisors (see below), whose sum is σ = 646676064. Its totient is φ = 646570000.

The previous prime is 646623023. The next prime is 646623059. The reversal of 646623031 is 130326646.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 130326646 = 2 ⋅65163323.

It is a cyclic number.

It is not a de Polignac number, because 646623031 - 2³ = 646623023 is a prime.

It is a super-2 number, since 2×646623031² = 836242688439253922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646622984 and 646623002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646623011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1986 + ... + 36016.

It is an arithmetic number, because the mean of its divisors is an integer number (161669016).

Almost surely, 2^646623031 is an apocalyptic number.

646623031 is a deficient number, since it is larger than the sum of its proper divisors (53033).

646623031 is a wasteful number, since it uses less digits than its factorization.

646623031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53032.

The product of its (nonzero) digits is 15552, while the sum is 31.

The square root of 646623031 is about 25428.7835139631. The cubic root of 646623031 is about 864.7363652454.

Adding to 646623031 its reverse (130326646), we get a palindrome (776949677).

The spelling of 646623031 in words is "six hundred forty-six million, six hundred twenty-three thousand, thirty-one".