340405631 has 4 divisors (see below), whose sum is σ = 347648352. Its totient is φ = 333162912.

The previous prime is 340405621. The next prime is 340405651. The reversal of 340405631 is 136504043.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 136504043 = 13 ⋅10500311.

It is a cyclic number.

It is not a de Polignac number, because 340405631 - 2¹⁸ = 340143487 is a prime.

It is a super-2 number, since 2×340405631² = 231751987233016322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 340405631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (340405601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3621290 + ... + 3621383.

It is an arithmetic number, because the mean of its divisors is an integer number (86912088).

Almost surely, 2^340405631 is an apocalyptic number.

340405631 is a deficient number, since it is larger than the sum of its proper divisors (7242721).

340405631 is an equidigital number, since it uses as much as digits as its factorization.

340405631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7242720.

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 340405631 is about 18450.0848507534. The cubic root of 340405631 is about 698.2306546359.

Adding to 340405631 its reverse (136504043), we get a palindrome (476909674).

The spelling of 340405631 in words is "three hundred forty million, four hundred five thousand, six hundred thirty-one".