21121400342 has 32 divisors (see below), whose sum is σ = 38260684800. Its totient is φ = 8548851168.

The previous prime is 21121400329. The next prime is 21121400401. The reversal of 21121400342 is 24300412112.

It is a super-2 number, since 2×21121400342² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 389717 + ... + 440592.

It is an arithmetic number, because the mean of its divisors is an integer number (1195646400).

Almost surely, 2^21121400342 is an apocalyptic number.

21121400342 is a deficient number, since it is larger than the sum of its proper divisors (17139284458).

21121400342 is a wasteful number, since it uses less digits than its factorization.

21121400342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 830420.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21121400342 its reverse (24300412112), we get a palindrome (45421812454).

The spelling of 21121400342 in words is "twenty-one billion, one hundred twenty-one million, four hundred thousand, three hundred forty-two".