21025401542 has 32 divisors (see below), whose sum is σ = 34000676640. Its totient is φ = 9714749440.

The previous prime is 21025401541. The next prime is 21025401547. The reversal of 21025401542 is 24510452012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21025401541) 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 15 ways as a sum of consecutive naturals, for example, 1761338 + ... + 1773234.

It is an arithmetic number, because the mean of its divisors is an integer number (1062521145).

Almost surely, 2^21025401542 is an apocalyptic number.

21025401542 is a deficient number, since it is larger than the sum of its proper divisors (12975275098).

21025401542 is a wasteful number, since it uses less digits than its factorization.

21025401542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12856.

The product of its (nonzero) digits is 3200, while the sum is 26.

Adding to 21025401542 its reverse (24510452012), we get a palindrome (45535853554).

The spelling of 21025401542 in words is "twenty-one billion, twenty-five million, four hundred one thousand, five hundred forty-two".