1906778688 has 56 divisors (see below), whose sum is σ = 5114166048. Its totient is φ = 626881536.

The previous prime is 1906778663. The next prime is 1906778707. The reversal of 1906778688 is 8868776091.

It is a super-2 number, since 2×1906778688² = 7271609930022002688, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54006 + ... + 82037.

Almost surely, 2^1906778688 is an apocalyptic number.

It is an amenable number.

1906778688 is an abundant number, since it is smaller than the sum of its proper divisors (3207387360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1906778688 is a wasteful number, since it uses less digits than its factorization.

1906778688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136131 (or 136121 counting only the distinct ones).

The product of its (nonzero) digits is 8128512, while the sum is 60.

The square root of 1906778688 is about 43666.6770890573. The cubic root of 1906778688 is about 1240.0335336058.

The spelling of 1906778688 in words is "one billion, nine hundred six million, seven hundred seventy-eight thousand, six hundred eighty-eight".