19420739 has 4 divisors (see below), whose sum is σ = 20914656. Its totient is φ = 17926824.

The previous prime is 19420733. The next prime is 19420741. The reversal of 19420739 is 93702491.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93702491 = 31 ⋅3022661.

It is a cyclic number.

It is not a de Polignac number, because 19420739 - 2²⁴ = 2643523 is a prime.

It is a super-2 number, since 2×19420739² = 754330206612242, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19420699 and 19420708.

It is not an unprimeable number, because it can be changed into a prime (19420733) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 746939 + ... + 746964.

It is an arithmetic number, because the mean of its divisors is an integer number (5228664).

Almost surely, 2^19420739 is an apocalyptic number.

19420739 is a deficient number, since it is larger than the sum of its proper divisors (1493917).

19420739 is a wasteful number, since it uses less digits than its factorization.

19420739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1493916.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 19420739 is about 4406.8967539528. The cubic root of 19420739 is about 268.7954526332.

The spelling of 19420739 in words is "nineteen million, four hundred twenty thousand, seven hundred thirty-nine".