21541208972 has 6 divisors (see below), whose sum is σ = 37697115708. Its totient is φ = 10770604484.

The previous prime is 21541208951. The next prime is 21541208999. The reversal of 21541208972 is 27980214512.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2692651118 + ... + 2692651125.

It is an arithmetic number, because the mean of its divisors is an integer number (6282852618).

Almost surely, 2^21541208972 is an apocalyptic number.

It is an amenable number.

21541208972 is a deficient number, since it is larger than the sum of its proper divisors (16155906736).

21541208972 is a wasteful number, since it uses less digits than its factorization.

21541208972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5385302247 (or 5385302245 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 41.

The spelling of 21541208972 in words is "twenty-one billion, five hundred forty-one million, two hundred eight thousand, nine hundred seventy-two".