31702421 has 2 divisors, whose sum is σ = 31702422. Its totient is φ = 31702420.

The previous prime is 31702387. The next prime is 31702439. The reversal of 31702421 is 12420713.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20884900 + 10817521 = 4570^2 + 3289^2 .

It is a cyclic number.

It is not a de Polignac number, because 31702421 - 2⁶ = 31702357 is a prime.

It is a super-2 number, since 2×31702421² = 2010086994522482, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31702393 and 31702402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31702921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15851210 + 15851211.

It is an arithmetic number, because the mean of its divisors is an integer number (15851211).

Almost surely, 2^31702421 is an apocalyptic number.

It is an amenable number.

31702421 is a deficient number, since it is larger than the sum of its proper divisors (1).

31702421 is an equidigital number, since it uses as much as digits as its factorization.

31702421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 31702421 is about 5630.4902983666. The cubic root of 31702421 is about 316.4930247775.

It can be divided in two parts, 31702 and 421, that added together give a palindrome (32123).

The spelling of 31702421 in words is "thirty-one million, seven hundred two thousand, four hundred twenty-one".