21275787442 has 16 divisors (see below), whose sum is σ = 39278377152. Its totient is φ = 8416794960.

The previous prime is 21275787431. The next prime is 21275787443. The reversal of 21275787442 is 24478757212.

It is not an unprimeable number, because it can be changed into a prime (21275787443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58449784 + ... + 58450147.

It is an arithmetic number, because the mean of its divisors is an integer number (2454898572).

Almost surely, 2^21275787442 is an apocalyptic number.

21275787442 is a deficient number, since it is larger than the sum of its proper divisors (18002589710).

21275787442 is a wasteful number, since it uses less digits than its factorization.

21275787442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116899953.

The product of its digits is 1756160, while the sum is 49.

The spelling of 21275787442 in words is "twenty-one billion, two hundred seventy-five million, seven hundred eighty-seven thousand, four hundred forty-two".