21401231331 has 16 divisors (see below), whose sum is σ = 29475145728. Its totient is φ = 13798017600.

The previous prime is 21401231233. The next prime is 21401231353. The reversal of 21401231331 is 13313210412.

It is not a de Polignac number, because 21401231331 - 2⁹ = 21401230819 is a prime.

It is a super-2 number, since 2×21401231331² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21401231298 and 21401231307.

It is not an unprimeable number, because it can be changed into a prime (21401231431) 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, 64375 + ... + 216671.

It is an arithmetic number, because the mean of its divisors is an integer number (1842196608).

Almost surely, 2^21401231331 is an apocalyptic number.

21401231331 is a deficient number, since it is larger than the sum of its proper divisors (8073914397).

21401231331 is a wasteful number, since it uses less digits than its factorization.

21401231331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153842.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 21401231331 its reverse (13313210412), we get a palindrome (34714441743).

The spelling of 21401231331 in words is "twenty-one billion, four hundred one million, two hundred thirty-one thousand, three hundred thirty-one".