21097261838 has 8 divisors (see below), whose sum is σ = 33311466120. Its totient is φ = 9993439800.

The previous prime is 21097261837. The next prime is 21097261847. The reversal of 21097261838 is 83816279012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21097261838² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21097261792 and 21097261801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21097261837) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 277595513 + ... + 277595588.

It is an arithmetic number, because the mean of its divisors is an integer number (4163933265).

Almost surely, 2^21097261838 is an apocalyptic number.

21097261838 is a deficient number, since it is larger than the sum of its proper divisors (12214204282).

21097261838 is a wasteful number, since it uses less digits than its factorization.

21097261838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 555191122.

The product of its (nonzero) digits is 290304, while the sum is 47.

The spelling of 21097261838 in words is "twenty-one billion, ninety-seven million, two hundred sixty-one thousand, eight hundred thirty-eight".