21237804558071 has 16 divisors (see below), whose sum is σ = 22719648268800. Its totient is φ = 19781814312960.

The previous prime is 21237804558067. The next prime is 21237804558109. The reversal of 21237804558071 is 17085540873212.

It is a cyclic number.

It is not a de Polignac number, because 21237804558071 - 2² = 21237804558067 is a prime.

It is a super-2 number, since 2×21237804558071² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21237804548071) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55213091 + ... + 55596411.

It is an arithmetic number, because the mean of its divisors is an integer number (1419978016800).

Almost surely, 2^{21237804558071} is an apocalyptic number.

21237804558071 is a deficient number, since it is larger than the sum of its proper divisors (1481843710729).

21237804558071 is a wasteful number, since it uses less digits than its factorization.

21237804558071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417034.

The product of its (nonzero) digits is 3763200, while the sum is 53.

The spelling of 21237804558071 in words is "twenty-one trillion, two hundred thirty-seven billion, eight hundred four million, five hundred fifty-eight thousand, seventy-one".