340021631 has 2 divisors, whose sum is σ = 340021632. Its totient is φ = 340021630.

The previous prime is 340021613. The next prime is 340021657. The reversal of 340021631 is 136120043.

Together with previous prime (340021613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is an emirp because it is prime and its reverse (136120043) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-340021631 is a prime.

It is a super-2 number, since 2×340021631² = 231229419095800322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (340021681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170010815 + 170010816.

It is an arithmetic number, because the mean of its divisors is an integer number (170010816).

Almost surely, 2^340021631 is an apocalyptic number.

340021631 is a deficient number, since it is larger than the sum of its proper divisors (1).

340021631 is an equidigital number, since it uses as much as digits as its factorization.

340021631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 340021631 is about 18439.6754580985. The cubic root of 340021631 is about 697.9680057748.

Adding to 340021631 its reverse (136120043), we get a palindrome (476141674).

The spelling of 340021631 in words is "three hundred forty million, twenty-one thousand, six hundred thirty-one".