21352312610 has 16 divisors (see below), whose sum is σ = 39472924536. Its totient is φ = 8310089088.

The previous prime is 21352312607. The next prime is 21352312679. The reversal of 21352312610 is 1621325312.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 21294689329 + 57623281 = 145927^2 + 7591^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21352312610.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28854107 + ... + 28854846.

Almost surely, 2^21352312610 is an apocalyptic number.

21352312610 is a deficient number, since it is larger than the sum of its proper divisors (18120611926).

21352312610 is a wasteful number, since it uses less digits than its factorization.

21352312610 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57708997.

The product of its (nonzero) digits is 2160, while the sum is 26.

Adding to 21352312610 its reverse (1621325312), we get a palindrome (22973637922).

The spelling of 21352312610 in words is "twenty-one billion, three hundred fifty-two million, three hundred twelve thousand, six hundred ten".