1920731 has 2 divisors, whose sum is σ = 1920732. Its totient is φ = 1920730.

The previous prime is 1920713. The next prime is 1920739. The reversal of 1920731 is 1370291.

Together with previous prime (1920713) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1920731 is a prime.

It is a super-2 number, since 2×1920731² = 7378415148722, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1920697 and 1920706.

It is not a weakly prime, because it can be changed into another prime (1920739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 960365 + 960366.

It is an arithmetic number, because the mean of its divisors is an integer number (960366).

2^1920731 is an apocalyptic number.

1920731 is a deficient number, since it is larger than the sum of its proper divisors (1).

1920731 is an equidigital number, since it uses as much as digits as its factorization.

1920731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 378, while the sum is 23.

The square root of 1920731 is about 1385.9043978572. The cubic root of 1920731 is about 124.3050717573.

The spelling of 1920731 in words is "one million, nine hundred twenty thousand, seven hundred thirty-one".