21434031 has 8 divisors (see below), whose sum is σ = 31754160. Its totient is φ = 14289336.

The previous prime is 21434029. The next prime is 21434047. The reversal of 21434031 is 13043412.

It is not a de Polignac number, because 21434031 - 2¹ = 21434029 is a prime.

It is a super-2 number, since 2×21434031² = 918835369817922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21433995 and 21434013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21434131) 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, 396900 + ... + 396953.

It is an arithmetic number, because the mean of its divisors is an integer number (3969270).

Almost surely, 2^21434031 is an apocalyptic number.

21434031 is a deficient number, since it is larger than the sum of its proper divisors (10320129).

21434031 is an equidigital number, since it uses as much as digits as its factorization.

21434031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 793862 (or 793856 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 21434031 is about 4629.6901624191. The cubic root of 21434031 is about 277.7801990841.

Adding to 21434031 its reverse (13043412), we get a palindrome (34477443).

The spelling of 21434031 in words is "twenty-one million, four hundred thirty-four thousand, thirty-one".