21146325506 has 8 divisors (see below), whose sum is σ = 31720225404. Its totient is φ = 10572917040.

The previous prime is 21146325503. The next prime is 21146325509. The reversal of 21146325506 is 60552364112.

It is an interprime number because it is at equal distance from previous prime (21146325503) and next prime (21146325509).

It can be written as a sum of positive squares in 2 ways, for example, as 16844146225 + 4302179281 = 129785^2 + 65591^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21146325503) 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, 16196 + ... + 206288.

Almost surely, 2^21146325506 is an apocalyptic number.

21146325506 is a deficient number, since it is larger than the sum of its proper divisors (10573899898).

21146325506 is a wasteful number, since it uses less digits than its factorization.

21146325506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245716.

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 21146325506 its reverse (60552364112), we get a palindrome (81698689618).

The spelling of 21146325506 in words is "twenty-one billion, one hundred forty-six million, three hundred twenty-five thousand, five hundred six".