349394640 has 80 divisors (see below), whose sum is σ = 1237861248. Its totient is φ = 79861248.

The previous prime is 349394627. The next prime is 349394657. The reversal of 349394640 is 46493943.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×349394640² = 244153228921459200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 349394592 and 349394601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 102307 + ... + 105666.

Almost surely, 2^349394640 is an apocalyptic number.

349394640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

349394640 is an abundant number, since it is smaller than the sum of its proper divisors (888466608).

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

349394640 is a wasteful number, since it uses less digits than its factorization.

349394640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207996 (or 207990 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 42.

The square root of 349394640 is about 18692.1010055050. The cubic root of 349394640 is about 704.3233384726.

The spelling of 349394640 in words is "three hundred forty-nine million, three hundred ninety-four thousand, six hundred forty".