1926961781 has 16 divisors (see below), whose sum is σ = 2154708864. Its totient is φ = 1713828864.

The previous prime is 1926961769. The next prime is 1926961787. The reversal of 1926961781 is 1871696291.

It is a cyclic number.

It is not a de Polignac number, because 1926961781 - 2¹⁰ = 1926960757 is a prime.

It is a super-2 number, since 2×1926961781² = 7426363410869383922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1926961787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2765 + ... + 62141.

It is an arithmetic number, because the mean of its divisors is an integer number (134669304).

Almost surely, 2^1926961781 is an apocalyptic number.

It is an amenable number.

1926961781 is a deficient number, since it is larger than the sum of its proper divisors (227747083).

1926961781 is a wasteful number, since it uses less digits than its factorization.

1926961781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59500.

The product of its digits is 326592, while the sum is 50.

The square root of 1926961781 is about 43897.1728132917. The cubic root of 1926961781 is about 1244.3934037400.

The spelling of 1926961781 in words is "one billion, nine hundred twenty-six million, nine hundred sixty-one thousand, seven hundred eighty-one".