21541097658 has 64 divisors (see below), whose sum is σ = 46889902080. Its totient is φ = 6572145600.

The previous prime is 21541097657. The next prime is 21541097671. The reversal of 21541097658 is 85679014512.

It is a happy number.

It is a super-2 number, since 2×21541097658² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21541097653) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2281788 + ... + 2291208.

It is an arithmetic number, because the mean of its divisors is an integer number (732654720).

Almost surely, 2^21541097658 is an apocalyptic number.

21541097658 is an abundant number, since it is smaller than the sum of its proper divisors (25348804422).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21541097658 is a wasteful number, since it uses less digits than its factorization.

21541097658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10123.

The product of its (nonzero) digits is 604800, while the sum is 48.

The spelling of 21541097658 in words is "twenty-one billion, five hundred forty-one million, ninety-seven thousand, six hundred fifty-eight".