21834020857 has 8 divisors (see below), whose sum is σ = 23826857760. Its totient is φ = 19842504960.

The previous prime is 21834020851. The next prime is 21834020863. The reversal of 21834020857 is 75802043812.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21834020851) and next prime (21834020863).

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

It is a cyclic number.

It is not a de Polignac number, because 21834020857 - 2¹¹ = 21834018809 is a prime.

It is a super-2 number, since 2×21834020857² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21834020851) 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, 295528 + ... + 361945.

It is an arithmetic number, because the mean of its divisors is an integer number (2978357220).

Almost surely, 2^21834020857 is an apocalyptic number.

It is an amenable number.

21834020857 is a deficient number, since it is larger than the sum of its proper divisors (1992836903).

21834020857 is a wasteful number, since it uses less digits than its factorization.

21834020857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660503.

The product of its (nonzero) digits is 107520, while the sum is 40.

The spelling of 21834020857 in words is "twenty-one billion, eight hundred thirty-four million, twenty thousand, eight hundred fifty-seven".