21260026731 has 8 divisors (see below), whose sum is σ = 28527255184. Its totient is φ = 14083074720.

The previous prime is 21260026709. The next prime is 21260026741. The reversal of 21260026731 is 13762006212.

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

It is not a de Polignac number, because 21260026731 - 2¹³ = 21260018539 is a prime.

It is a super-2 number, since 2×21260026731² (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 (21260026741) 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, 22568560 + ... + 22569501.

It is an arithmetic number, because the mean of its divisors is an integer number (3565906898).

Almost surely, 2^21260026731 is an apocalyptic number.

21260026731 is a deficient number, since it is larger than the sum of its proper divisors (7267228453).

21260026731 is a wasteful number, since it uses less digits than its factorization.

21260026731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45138221.

The product of its (nonzero) digits is 6048, while the sum is 30.

The spelling of 21260026731 in words is "twenty-one billion, two hundred sixty million, twenty-six thousand, seven hundred thirty-one".