1901531 has 2 divisors, whose sum is σ = 1901532. Its totient is φ = 1901530.

The previous prime is 1901519. The next prime is 1901551. The reversal of 1901531 is 1351091.

It is an a-pointer prime, because the next prime (1901551) can be obtained adding 1901531 to its sum of digits (20).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1901531 - 2¹⁸ = 1639387 is a prime.

It is a super-2 number, since 2×1901531² = 7231640287922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1901551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 950765 + 950766.

It is an arithmetic number, because the mean of its divisors is an integer number (950766).

2^1901531 is an apocalyptic number.

1901531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1901531 is an equidigital number, since it uses as much as digits as its factorization.

1901531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 135, while the sum is 20.

The square root of 1901531 is about 1378.9601154493. The cubic root of 1901531 is about 123.8894913811.

The spelling of 1901531 in words is "one million, nine hundred one thousand, five hundred thirty-one".