21402142516 has 12 divisors (see below), whose sum is σ = 38367255780. Its totient is φ = 10440069440.

The previous prime is 21402142453. The next prime is 21402142529. The reversal of 21402142516 is 61524120412.

It can be written as a sum of positive squares in 2 ways, for example, as 2581046416 + 18821096100 = 50804^2 + 137190^2 .

It is a super-3 number, since 3×21402142516³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65250271 + ... + 65250598.

It is an arithmetic number, because the mean of its divisors is an integer number (3197271315).

Almost surely, 2^21402142516 is an apocalyptic number.

It is an amenable number.

21402142516 is a deficient number, since it is larger than the sum of its proper divisors (16965113264).

21402142516 is a wasteful number, since it uses less digits than its factorization.

21402142516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130500914 (or 130500912 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

Adding to 21402142516 its reverse (61524120412), we get a palindrome (82926262928).

The spelling of 21402142516 in words is "twenty-one billion, four hundred two million, one hundred forty-two thousand, five hundred sixteen".